JPS63116850A - Vapor permeable and waterproof two-component structure - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-component structure for use as a surgical sterile cloth and in waterproof garments and equipment.

The textile industry produces so-called breathable textiles consisting of films of water vapor permeable polymeric materials bonded to textile materials. The most famous and successful water vapor permeable material is a film of microporous polytetrafluoroethylene bonded to a textile material. Although this product has been eminently successful, it is quite expensive and its pores tend to become clogged by dust, body oils and detergents. Other polymers such as nylon or poly(ethylene terephthalate) also have high water vapor permeability and can be used to produce waterproof and water vapor permeable garments when coated with textile materials such as nylon or polyethylene terephthalate. It is known. US Special Note No. 4.493.8
No. 70 is made from dicarboxylic acids, aliphatic diols and poly(alkylene oxide) glycols. A waterproof garment is disclosed provided that at least 70% of the glycol is made from a textile material coated with a monolayer film of a copolyetherester having a carbon to oxygen ratio of 2.0 to 2.4. Such waterproof garments as described herein exhibit water vapor transmission rate values that are absent on the film surface facing the high humidity side. The resulting value will be the same no matter which side is exposed to the same value. There is a need for a waterproof, water vapor permeable product that transports water vapor at a slower rate for a product that protects from outside water than from inside. For example, shoes or boots made from such products that have the ability to transfer water vapor from the interior at a faster rate to ensure comfort are subject to US No. 4.493 under external wet conditions. It will keep the wearer's feet drier than the product disclosed in '870.

Up to the time of the present invention, the water vapor transmission rate of water vapor permeable layers of articles such as raincoats has been substantially the same in either direction. Japanese Special Application No. 50-35623, dated October 1, 1976, discloses a water vapor permeable product of a single layer film of copolyetherester elastomer coated with a textile material. The teachings of this Japanese special note have the same drawbacks as that of U.S. special note 4.493.870,
For example, water vapor permeable products have the drawback of transmitting water vapor at the same rate from each side of the sheet or film when exposed to the same degree of humidity. As a surgical sterile cloth and through the film, it quickly transmits water vapor to the outside or to the ambient air side of the garment or product, but minimizes the transmission of water in the opposite direction, protecting the wearer from water, liquids and vapors from external sources. An easily fabricated and inexpensive waterproof and water vapor permeable material for use in waterproof clothing or products that has the greatest advantage of increasing the transmission of water vapor out of the wearer while providing protection and making the clothing or product comfortable. film is technically required.

The present invention provides: (A) a thickness of 0.05 to 0.8 mil and an ASTM
400-25 according to E96-66 (No. BW Law)
a continuous layer of a hydrophobic elastomer having a water vapor transmission rate of 00 g-mil/m''/24 hours, provided that the hydrophobic elastomer comprises a large number of repeating long-chain ester units and short-chain ester units linked head-to-tail through ester linkages. a copolyetherester elastomer or a mixture of two or more copolyetherester elastomers, the long chain ester units having the formula % and the short chain ester units having the formula -OD〇 -CR
C-(II), where G is an average molecular weight of about 400-350
is the divalent group remaining after removal of the terminal hydroxyl group from a poly(alkylene oxide) glycol having 0 and is further present in a copolyetherester or a mixture of two or more copolyetheresters
The amount of ethylene oxide groups introduced by the (alkylene oxide) glycol is not more than about 20% by weight, based on the total weight of the copolyetherester or mixture of two or more copolyetheresters: R has a molecular weight less than 300; D is the divalent group remaining after removing the carboxyl group from the dicarboxylic acid; D is the divalent group remaining after removing the hydroxyl group from the diol having a molecular weight of less than about 250; and the hydrophobic copolyether ester or The mixture of species or more copolyetheresters has about 25 to 80% by weight short chain ester units; (B) has a thickness of 0.3 to 6 mils and is ASTM E
96-66° (No. BW Law) at least 3500°
a continuous phase of a hydrophilic elastomer having a water vapor transmission rate of g.mil/m2/24 hours, provided that the hydrophilic elastomer is head-to-tail bonded through ester bonds represented by formulas (I) and (I[); a polyetherester elastomer containing a large number of long-chain ester units and short-chain ester units having the abovementioned values or a mixture of two or more copolyetherester elastomers, where the copolyetherester or two or more copolyetherester elastomers The amount of ethylene oxide groups introduced by the poly(alkylene oxide) glycol into the mixture of more copolyetheresters is from about 25 to 68% by weight and the hydrophilic copolyetherester or mixture of two or more copolyetheresters contains about 25% by weight.
~80% by weight of short-chain ester units; hydrophobic and hydrophilic layers of copolyetherester elastomer bonded together to allow differential movement of water vapor to prevent moisture build-up; layer, ASTM E-96-6
6 (Method BW) having a separation ratio to water vapor of at least 1.2.

The ethylene oxide group in the copolyether ester elastomer refers to (CH2-CH, -〇-
) refers to the weight percent of the group in the total elastic body.

The ethylene oxide groups in the copolyether ester that are counted to determine the amount in the polymer are derived from poly(alkylene oxide) glycols, with ethylene oxide being able to be introduced into the copolyether ester by means of low molecular weight diols. Not a base.

The water vapor separation ratio is as per ASTM E-96-66 (Part B
The measurements were carried out at 22°C as described in W method),
The value of the water vapor permeability rate obtained by placing the hydrophilic layer of the two-component film next to the water surface is the value of the water vapor permeability rate obtained by placing the hydrophobic layer of the two-component film next to the water surface. means the value divided by The presence of a woven fabric on a two-component film has no effect on the separation ratio value of the film.

The two-component film is particularly useful as a surgical sterile cloth used to cover a patient's body during surgery to reduce the possibility of bacterial infection. Bicomponent films can also be bonded to woven fabrics through a hydrophobic layer to make moisture vapor permeable products such as raincoats, jackets, tents, wetsuits, protective clothing, gloves, shoes, boots, car covers, etc. breathable. Particularly suitable for

The two-component film of the present invention conforms to ASTM E-96-6
6 (Method BW), water vapor is
A much higher water vapor transmission rate (WVTR) in the direction of the hydrophilic layer of the film and then through the hydrophobic layer of the two-component film than from the hydrophobic layer of the film and then through the hydrophilic layer of the film. shows. The two-component film structure of the present invention is used as a surgical sterile cloth and the hydrophilic layer of the film is placed next to the patient's skin (in the case of a sterile surgical cloth next to a wound or on the patient's skin). Water vapor accumulation can be substantially reduced due to the high rate of water vapor transmission from the hydrophilic layer through the hydrophobic layer.The non-porous nature of the two-component film reduces the possibility of infection caused by soiling of the area. Furthermore, the high rate of water vapor transmission of the hydrophilic layer makes it useful when the two-component film is used in garments such as raincoats, jackets and shoe linings.
When a component film is used in the manufacture of a raincoat and the textile material is adhered to the hydrophobic layer of the film by melt bonding or adhesive bonding, the rate of water vapor transmission from the hydrophilic layer of the film to the hydrophobic layer of the film and the hydrophobic The water vapor flow through the polar layer is substantially higher than in the opposite direction. As a result, the wearer of the raincoat is aware that water vapor that accumulates on the inside of the coat next to the hydrophilic layer of the two-component film is
It is more comfortable because it is smaller than the amount that would accumulate if it were approximately the same in each direction.

"Long chain ester units" as applied to units of polymer chains
refers to the reaction products of long-chain glycols with dicarboxylic acids. The "long chain ester unit" which is a repeating unit of the copolyetherester of the present invention corresponds to the above formula (I). Long chain glycols are polymeric glycols having terminal (or as nearly terminal as possible) hydroxy groups.

The molecular weight of the polymeric glycol used to make the copolyetherester for hydrophobic or hydrophilic films is about 400-3500.

The poly(alkylene oxide) glycol used to produce the hydrophobic copolyetherester elastomer is
It can contain ethylene oxide groups such that the total weight is up to about 20% by weight of the total weight of the polymer. In many cases, the poly(alkylene oxide) glycols used to make such copolyetheresters do not contain ethylene oxide, and the resulting copolyetheresters do not contain ethylene oxide residues. However, based on elastic bodies, at most 20
The poly(alkylene oxide) glycol containing ethylene oxide groups in an amount that does not result in a copolyetherester having ethylene oxide groups of not more than 15% by weight, preferably not more than 15% by weight, is such that the resulting copolyetherester has a sufficiently low Approximately 2500g・mil/m”/
It can be used because it exhibits a water vapor permeability no greater than 24 hours. A typical poly(alkylene oxide) glycol that can be used to form the long chain ester units of the hydrophobic copolyetherester is 400
~3500, usually 600-1500, and poly(1,2- and 1,3-propylene oxide)
Random or block copolymers of glycol, poly(tetramethylene oxide) glycol, ethylene oxide and 1,2-propylene oxide in appropriate proportions, and tetrahydrofuran, random or block, with small amounts of second monomers, such as methyltetrahydrofuran. Contains block copolymers. However, the content of ethylene oxide is such as to produce a copolyetherester having at most 20% by weight of ethylene oxide groups. Preferably, the poly(alkylene oxide) glycol used to make the hydrophobic film is poly(tetramethylene ether) glycol or ethylene oxide terminated polypropylene oxide glycol.

The poly(alkylene oxide) glycol used to make the woody copolyether ester is about 25 to 6
8! The copolyether ester must contain ethylene oxide groups in an amount sufficient to yield a copolyether ester having % ethylene oxide groups. This ethylene oxide group gives the polymer the property of easily transmitting water vapor. Generally, the higher the percentage of ethylene oxide in the copolyetherester, the higher the degree of water vapor transmission. Random or block copolymers of ethylene oxide containing small amounts of a second poly(alkylene oxide) glycol can also be used. Generally, if the second monomer is present, it will constitute no more than about 30 mole percent, and usually no more than about 20 mole percent, of the poly(alkylene oxide) glycol. Typical long chain glycols used to produce copolyetheresters that form hydrophilic films have a molecular weight of 400 to 350
0, usually having a molecular weight of 600 to 1500, and poly(ethylene oxide) glycol, polypropylene oxide glycol terminated with ethylene oxide;
Includes mixtures of poly(ethylene oxide) glycol with other glycols such as ethylene oxide-terminated poly(propylene oxide) glycol and/or poly(tetramethylene oxide) glycol. However, in this case, the copolyether ester obtained is at least 2
It has an amount of ethylene oxide groups of 5% by weight. Approximately 60
Copolyether esters made from ethylene oxide glycol having a molecular weight of 0 to 1500 are preferred as they have a combination of excellent water vapor permeability and limited water swelling and can be formed into films. It exhibits useful properties over a wide temperature range.

"Short chain ester units" as applied to units in the polymer chains of copolyether esters forming the hydrophobic or hydrophilic layers of a two-component film are low molecular weight compounds or polymer chains having a molecular weight of about 500 or less. It is about units. They are low molecular weight diols or diols (molecular weight approximately 250
The mixture of the above formula (II) is reacted with a dicarboxylic acid.
) is produced to form an ester bond.

Preferably, the copolyetherester of hydrophobic and hydrophilic elastomer has a melting point of greater than 120°C, usually from about 120°C to greater than about 220°C. If the melting point of the copolyether ester is below about 120°C, the polymer becomes sticky and difficult to handle in film form. Melting point is about 2
Above 20°C, the film becomes too stiff. Melting points are determined with differential scanning calorimetry (D SC).

Among the low molecular weight diols that can be reacted to form short chain ester units suitable for producing copolyetheresters forming either the hydrophobic or hydrophilic layer of a two-component film are acyclic , cycloaliphatic and aromatic dihydroxy compounds. The preferred compound has 2 carbon atoms.
-15 diols such as ethylene, propylene, imbutylene, tetramethylene, 1,5-pentamethylene, 2
, 2-dimethyltrimethylene, hexamethylene and decamethylene glycol, dihydroxycyclohexane,
Contains cyclohexane dimetatool, resorcinol, hydroquinone, 1,5-dihydroxynaphthalene, etc. Particularly preferred diols are aliphatic diols having 2 to 8 carbon atoms, most especially 1,4-butanediol. Bisphenols that can be used include bis(p- and hydroxy)diphenol, bis(p-hydroxyphenyl)methane, and bis(p-hydroxyphenylpropane).

Esterogenic derivatives thereof equivalent to diols are also useful (eg, ethylene oxide or ethylene carbonate can be used in place of ethylene glycol). As used herein, "low molecular weight diol" is to be considered to include such equivalent ester-forming derivatives. However, the molecular weight requirement concerns the diol and not its derivatives.

The dicarboxylic acids that react with the aforementioned long chain glycols and low molecular weight diols to form copolyether esters that can be used for both the hydrophobic and hydrophilic properties of the two-component films of the present invention are of low molecular weight, i.e. It is an aliphatic, alicyclic or aromatic dicarboxylic acid having a molecular weight of 300 or less. As used herein, "dicarboxylic acid" refers to the acid equivalent of a dicarboxylic acid having a difunctional carboxyl group that functions substantially like a dicarboxylic acid in reaction with glycols and diols in the preparation of copolyetherester polymers. including. These equivalents include esters and ester-forming derivatives such as acid halides and acid anhydrides.The molecular weight requirements are with respect to the acid and not with respect to the equivalent ester or ester-forming derivative thereof. Thus, esters of dicarboxylic acids having a molecular weight greater than 300 or acid equivalents of dicarboxylic acids having a molecular weight greater than 300 may also be included if the acid has a molecular weight of 300 or less. The dicarboxylic acid may contain any substituent or combination that does not substantially interfere with the preparation of the copolyetherester polymer and the use of the polymer in the compositions of the present invention.

Aliphatic dicarboxylic acids, as used herein, relate to carboxylic acids having two carboxyl groups, each attached to a saturated carbon atom.

If the carbon atom to which the carboxyl group is attached is saturated and present in a ring, the acid is alicyclic. Aliphatic or cycloaliphatic acids with conjugated unsaturation often cannot be used for homopolymerization.

However, some unsaturated acids can be used, such as maleic acid.

Aromatic dicarboxylic acids, as used herein, are dicarboxylic acids in which two carboxyl groups are attached to carbon atoms of a carbocyclic aromatic ring. It is not necessary that both functional carboxyl groups are attached to the same aromatic ring, and if more than one ring is present, they may be aliphatic or aromatic divalent groups or monovalent groups. 〇- or -8○2-
They may be linked by a divalent group such as.

Representative aliphatic and cycloaliphatic acids that may be used include sebacic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, adipic acid, geltaric acid,
4-Cyclohexane-1,2-dicarboxylic M, 2-ethylsperinic acid, cyclopentanedicarboxylic acid, decahydro-2,6-naphthalene dicarboxylic acid, 4,4'-methylenebis(cyclohexyl)carboxylic acid, 3,4-furandicarboxylic acid It is. Preferred acids are cyclohexane-dicarboxylic acid and adipic acid.

Representative aromatic dicarboxylic acids that can be used to make the copolyetheresters used to make the film are phthalic acid, terephthalic acid, isophthalic acid, bisbenzoic acid, substituted dicarboxylic compounds with two benzene nuclei such as bis (p-carboxyphenyl)methane, p-oxy-1,5-naphthalene dicarboxylic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid,
4.4'-Sulfonylbisbenzoic acid and their CIs
"" CI 2-alkyl and ring-substituted derivatives such as halo,
Includes alkoxy and aryl derivatives. Hydroxy acids such as p-(β-hydroxyethoxy)benzoic acid can also be used if aromatic dicarboxylic acids are present.

Aromatic dicarboxylic acids are a preferred type for making copolyetherester polymers useful in making the two-component films of the present invention. Aromatic acids.

Therefore, those having 8 to 16 carbon atoms, particularly terephthalic acid alone or a mixture thereof with phthalic acid and/or isophthalic acid, are suitable.

As mentioned above, the copolyetherester elastomer forming the hydrophilic layer of the two-component film is similar to the copolyetherester elastomer forming the hydrophobic layer of the two-component film, except for the ethylene oxide groups in the copolyetherester. It is. In the above formula (I), G for the woodphilic copolyetherester or the hydrophobic copolyetherester is a divalent group remaining after removing the terminal hydroxyl group from the poly(alkylene oxide) glycol having a molecular weight of about 400 to 3500. . The poly(alkylene oxide) glycol used for the wood-philic copolyester is
The resulting copolyether ester is approximately 25-68% by weight.
, preferably containing enough ethylene oxide groups to have an ethylene oxide content of about 30-55% by weight. The poly(alkylene oxide) glycols used for the hydrophobic copolyesters have an ethylene oxide content of 0 to 20% by weight.

The copolyetherester used to produce the hydrophilic layer of the two-component film of the present invention contains about 25-80% by weight, preferably about 40-60% by weight of short-chain ester units corresponding to formula (I[) above. The remainder is a long chain ester unit corresponding to the above formula (I). The copolyetherester elastomer used in the hydrophilic layer of the two-component film is approximately 25%
When containing less than % by weight of short chain ester units, the crystallization rate becomes very slow and the copolyether ester becomes sticky and difficult to handle. If the copolyetherester elastomer used in the hydrophilic layer contains more than about 80% by weight short chain ester units, the copolyetherester film becomes too stiff.

The preferred balance of properties is that the short chain ester units are about 40 to
Obtained at 60% by weight.

The copolyether ester used to make the hydrophobic layer of the two-component film having a thickness of 0.05 to 0.8 mil contains about 25 to 8 short chain ester units corresponding to formula (II) above.
It is contained in an amount of 0% by weight, preferably about 30 to 60% by weight, and the remainder is a long chain ester unit corresponding to the above formula (I). Generally, as the percentage of short chain ester units in the copolyether ester increases, the polymer has higher tensile strength and modulus and the water vapor transmission rate decreases. Most preferably, for both copolyetheresters forming the hydrophilic and hydrophobic layers of the two-component film, at least about 70% of the groups represented by R in formulas CI) and (II) above are 1.4- is a phenylene group, and has the above formula (
At least 70% of the groups represented by D in II) are 1,4
- R groups and l which are butylene groups and are not 1,4-phenylene groups.

The total percentage of D groups that are not 4-butylene groups is 30%
not exceed. Isophthalic acid is the acid of choice if a second dicarboxylic acid is used to make the copolyetherester, and 1,4-butanediol or hexamethylene glycol is the acid of choice if a second base molecular weight diol is used. It is a diol that can be used.

The hydrophobic and hydrophilic layers of the two-component film may be a blend or mixture of two or more copolyetherester elastomers. The copolyether ester used in the blend need not fall within the range mentioned above for the elastomer on an individual basis. However, the blend of two or more copolyetherester elastomers forming either the hydrophobic layer or the hydrophilic layer must, on a weight average basis, match the values stated above for the copolyetherester. It won't happen. For example, if the mixture is used to produce a hydrophilic layer of a two-component film containing equal amounts of two copolyetherester elastomers, 1
One copolyetherester may contain 60% by weight of short chain ester units and the other copolyetherester may contain 30% by weight for a weight average of 45% by weight of short chain esters in the hydrophilic layer of the two-component film. %
short-chain ester units.

The water vapor transmission rate of the hydrophobic and hydrophilic layers that make up the two-component film can be adjusted by various means. Obviously, the thickness of the copolyetherester layer influences the water vapor transmission rate, the thinner the layer, the higher the value. An increase in the percentage of short-chain ester units of the copolyether ester used to produce the layers of the two-component film decreases the value of the water vapor transmission rate, but due to the fact that the polymer becomes more crystalline, the layer Increase the tensile strength value of. The water vapor permeation rate through a normal hydrophobic layer is 40 according to ASTM E96-66 (Part BW method).
0-2500g・mil/m2/24 hours, preferably 80
0 to 1200 g・mil/m 2/24 hours. Water vapor transmission rate through the hydrophilic layer is ASTM E96-6
6 (Method BW) at least 3500 g mil/m”/24 hours, preferably 3500 to 20,000 g
- Mil/m z724 hours.

The Young's modulus of the copolyetherester elastomer used to make the hydrophobic and hydrophilic layers is between 1000 and 14,0 as determined by ASTM method D-412.
00psi, usually 2000-10°000psi. This Young's modulus can be controlled by the ratio of short to long chain segments of the copolyetherester elastomer and the selection of comonomers for the preparation of the copolyetherester. The importance of using copolyetheresters with a relatively low Young's modulus is the good stretch recovery and aesthetic appearance of the composite when bonded to textile materials for the manufacture of garments, e.g. jackets and raincoats; Garment stiffness and sterility are also important for comfort.

The most preferred copolyether ester volatiles used to prepare the hydrophilic layer of the two-component film are those prepared from esters of terephthalic acid such as dimethyl terephthalate, 1,4-butanediol and poly(ethylene oxide) glycol. It is something. The most preferred copolyetherester elastomers used to produce the hydrophobic layer of the two-component film are esters or ester mixtures of terephthalic acid and isophthalic acid, l,4-butanediol and poly(tetramethylene ether) glycol or It is manufactured from polypropylene oxide glycol terminated with ethylene oxide.

The dicarboxylic acid or derivative thereof and the polymeric glycol are introduced into the final product in the same molar proportions as present in the reaction mixture. The amount of low molecular weight diol actually introduced corresponds to the difference in the number of moles of diacid and polymeric glycol present in the reaction mixture. When using mixtures of low molecular weight diols, the amount of each diol introduced is primarily a function of the amount of diol present, its boiling point, and relative reactivity.

The total amount of glycol introduced is the difference in moles of diacid and polymeric glycol. The copolyetherester elastomers used to make the hydrophobic and hydrophilic layers of the two-component films described herein can be conveniently made by conventional transesterification reactions. A preferred method is to convert an ester of an aromatic acid, such as the dimethyl ester of terephthalic acid, to poly(ethylene oxide) in the presence of a catalyst.
Glycol and molar excess of low molecular weight diol, 1°4
- heating to 150-260° C. with butanediol, followed by distilling off the methanol produced by the exchange reaction. Heating is continued until methanol generation is complete. Depending on temperature, catalyst and glycol excess,
This polymerization is complete within minutes to hours. The product leads to the production of low molecular weight prepolymers which can be combined with high molecular weight copolyetheresters by the methods described above. Such prepolymers can be produced by many other esterification or transesterification methods;
For example, long chain glycols can be reacted with high or low molecular weight short chain ester homopolymers or copolymers in the presence of a catalyst until randomization occurs. Short chain ester homopolymers or copolymers can be prepared by transesterification from dimethyl ester and low molecular weight diols or from free acid and diol acetate, as described above.

Alternatively, short chain ester copolymers can be prepared by direct esterification of suitable acids, acid anhydrides or acid chlorides, for example with diols, or by other methods such as reaction of acids with cyclic ethers or carbonates. Obviously, prepolymers can also be prepared by carrying out these steps in the presence of long chain glycols.

The resulting prepolymer can subsequently be made to high molecular weight by distilling off excess short chain diols. This method is known as "F polycondensation". During this distillation, further transesterification occurs, increasing the molecular weight and randomizing the arrangement of the copolyether ester units. Best results usually occur when this final distillation or polycondensation is combined with an antioxidant such as l,6-bis[(3,5-di-tert-butyl-4-
hydroxyphenol)-propionamide] -hexane or 1,3.5-1-limethyl-2,4,6-tris[3,5-di-tert-butyl-4-hydroxybenzyl]benzene at a pressure of less than 1 mm. and 240
obtained when carried out at ~260°C for up to 2 hours. The most practical polymerization method is transesterification to complete the polymerization reaction.

In order to avoid excessive holding times at high temperatures due to the possibility of irreversible thermal decomposition, it is advantageous to use a catalyst for the transesterification reaction. Although a variety of catalysts may be used, it is preferred to use organic titanates such as tetrabutyl titanate alone or in combination with magnesium or calcium carbonate. Complex titanates derived from, for example, alkali or alkaline earth metal alkoxides and titanate esters are also very effective. Inorganic titanates such as lanthanum titanate, calcium acetate/antimony trioxide mixtures, and lithium and magnesium alkoxides are representative of other catalysts that may be used.

Transesterification polymerizations are generally carried out in the melt without added solvent, although inert solvents may be used to facilitate the removal of volatile components from the reactants at low temperatures. This method is particularly useful during the production of prepolymers, for example by direct esterification.

However, certain low molecular weight diols such as butanediol can be conveniently removed during polymerization by azeotropic distillation.

Other special polymerization methods are useful for making special polymers, such as interfacial polymerization of bisphenols with bisacyl halides and bisacyl halide-terminated linear diols. Batch and continuous processes can be used for any stage of copolyetherester polymer production.

Polycondensation of the prepolymer may be carried out in the solid phase by heating the finely divided solid prepolymer under vacuum or in a stream of inert gas to remove liberated low molecular weight diols. This process has the advantage of reducing decomposition since it must be used at temperatures below the softening point of the prepolymer. The main drawback is the long time required to achieve the desired polymerization.

Although copolyetheresters have many desirable properties, it is sometimes advantageous to further stabilize these compositions against thermal or light degradation. It's lucky that,
This can be done very easily by incorporating stabilizers into the copolyetherester. Satisfactory stabilizers include phenols, especially sterically hindered; phenols and their derivatives; amines and their derivatives, especially arylamines.

A typical phenol derivative useful as a stabilizer is 4.4'
-bis(2,6-tert-butylphenol);
1,3,5-1-dimethyl-2,4,6-tris[3
,5-di-tert-butyl-4-hydroxybenzyl]benzene and 1,6-bis(3,5-di-tert-butyl-4-hydroxybenzyl)
-7'Tyl-4-hydroxyphenyl)propionamide]-hexane. Mixtures of sterically hindered phenols with co-stabilizers such as dilaurylthiodipropionate or phosphites are particularly useful. The light stability is improved by adding small amounts of pigments or by introducing light stabilizers such as benzotriazole UV absorbers. Hindered amine light stabilizers, such as bis(1,2,2,
Addition of 6°6-bentamethyl-4-piperidinyl) n-butyl-(3,5-di-tert-butyl-4-hydroxybenzyl) malonate in an amount of 0.05 to 1.0% by weight of the normal copolyether ester. are particularly useful for producing compositions that are resistant to photodegradation.

Various conventional fillers can be added to the copolyetherester, usually in an amount of about 1-10% by weight of the copolyetherester or mixture of copolyetheresters forming the layer of the two-component film. Fillers such as clay, talc, alumina, carbon black, silica can be used, the latter being preferred. White and light colored pigments may also be added to the polymer. Generally, these additives have the effect of increasing Young's modulus at various stretches.

Inorganic fillers can be added in finely divided form to the woodphilic copolyether esters used to improve the sliding and blocking properties of hydrophilic layers, such as clothing, without sacrificing the adhesive integrity of the layer to the textile material. It would be advantageous to provide improved sewability and aesthetics.

Any suitable textile material used for the manufacture of weather layers, jackets, protective clothing, tents, etc. can be adhered to the hydrophobic layer of the two-component film, preferably by melt bonding or adhesive bonding.

The hydrophobic layer is an essential part of the two-component film. The hydrophobic layer covers one surface of the hydrophilic layer forming the two-component film. This hydrophobic layer serves as a means to adjust the WVTR separation ratio and facilitates adhesive bonding to textile materials compared to bonding single layer films of hydrophilic materials. Also, if the polymer forming the hydrophobic layer has a sufficiently lower melting point (melting point at least about 10°C or less) than the copolyetherester forming the hydrophilic phase, it will not soften the high melting hydrophilic layer and It can also function as an adhesive for bonding textile materials, ie woven or non-woven, to themselves while maintaining the integrity of the two-component film to form a flexible layered product that can be processed into garments and the like. Additionally, the copolyetherester hydrophilic layer of the film that is coextruded with the hydrophilic layer of the film provides strong adhesion between the layers due to the chemical similarity of the copolyetherester elastomer forming the two-component film. Commonly used textile materials are polyethylene terephthalate, or polyamides such as nylon 6 or 66, cotton, and cellulose triacetate. The textile material can be attached or adhered to the hydrophobic layer of the two-component film to produce a layered product.

To make textile materials more water repellent, conventional substances such as fluorocarbons and silicones can be coated or sprayed onto the textiles.

The composite structure of a hydrophobic layer of a two-component film, a hydrophobic layer of the film, and a hydrophilic layer of the film provides for the passage of water vapor first through the hydrophilic layer and then through the hydrophobic layer, such that the water vapor source is A much larger WVTR than when passing through the adjacent layers first the hydrophobic layer and then the hydrophilic layer.
bring about.

Garments made from the two-component film have a hydrophilic layer on the inside next to the wearer, and therefore the WVTR is higher in the direction from the hydrophilic layer to the hydrophobic layer, giving a desirable cooling effect to the wearer of the garment. . Such clothing blocks out snow and rain while maintaining ventilation.

The hydrophobic and hydrophilic layers forming the two-component film of the invention behave like permeability valves. The permeability of two-component film structures is not linear with vapor pressure (relative humidity). As the relative humidity increases, the hydrophilic layer absorbs water in an amount determined by its swellable and permeable composition. The higher the weight percent of long chain ester units in the copolyether ester, the higher the water swellability of the polymer. As a result, when the hydrophilic layer of a two-component film is next to a water source, the water vapor transmission rate value is about 2-3 times higher than when the hydrophobic layer is next to a water source. Hydrophobic copolyetherester elastomer and wood-philic copolyetherester elastomer 2
The component films are manufactured by conventional coextrusion techniques.

The chemical similarity in structure, composition and melt viscosity behavior of the copolyetherester elastomers has excellent glabella adhesion.

Provides a uniform layer of two-component film.

Briefly, the method for producing two-component films by coextrusion is as follows. The copolyetherester forming the hydrophilic layer of the two-component film and additives, if present, are fed into one extruder, and the copolyetherester forming the hydrophobic layer and additives, if present, are fed into a second extruder.
feed to the extruder. The polymer in the extruder is heated above its melting point. However, this should differ by at least about 10°C when melt bonding the textile material to the hydrophobic layer. Each layer is then passed through a conventional melt coalescing block connected to an extruder, where one of the extruded layers is brought into contact over the other layer. The layers are then passed through a flat die connected to the coalescing block, where the coextruded layers are adhered to each other to produce a two-component film structure. The two-component film emerging from the die is melt-coated onto a support material such as lightweight polyester film, release paper, etc., and the two-component film is then wound and stored for use. This 2
The component film can be used as a surgical sterilization cloth.

If the two-component film structure is desired to be made into a material for processing into raincoats, jackets or other garments, the two-component film is placed on a hot roll calendering device, with the hydrophobic layer of the film adjacent to the textile material. The two-component film is bonded to a textile material, such as poly(ethylene terephthalate), by thermally laminating the film to a textile material such as poly(ethylene terephthalate). Briefly, one such method is as follows. The temperature used to bond the textile material to the hydrophobic layer of the two-component film is sufficient to melt the hydrophobic layer but not the hydrophilic layer, and sufficient pressure is applied to bond the layer. Join. The resulting flexible layered product can be made into clothing, tents, etc.

The following examples illustrate the invention. In the examples and percentages are by weight unless otherwise specified.

Examples: Ingredients used: Copolyetherester A forming the hydrophilic layer of the film contains 49.9% by weight of 1.4-butylene terephthalate.
and poly(ethylene oxide) terephthalate 50.1
% by weight and the poly(alkylene oxide) glycol used to make this copolyetherester had a molecular weight of 1450. This copolyetherester had a calculated ethylene oxide content of 46.0% by weight and contained 49.9% by weight of short chain ester units. The polymer has a melting point of 194°C and a weight of 18.500 g.
・mil/m”/24 hour water vapor transmission rate (WVT
R).

Copolyetherester B forming the hydrophobic layer of the film contains 38% by weight of l,4-butylene terephthalate, l
, 4-butylene isoterephthalate 11% by weight, poly(
It contained 39.6% by weight of tetramethylene ether) terephthalate and 11.4% by weight of poly(tetramethylene ether)in 7-talate. The poly(alkylene oxide) glycol used to make this copolyetherester had a molecular weight of 1000. The ethylene oxide content of this copolyetherester was zero. The polymer contained 49% by weight short chain ester units and had a melting point of 148°C and a WVTR of 450 g·mil/m''/24 hours.

The copolyetherester C forming the hydrophobic layer of the film is 1.4-7' ethylene terephthalate 20.311
J1%, l,4-butylene isophthalate 7.9% by weight
, 51.7% by weight of poly(tetramethylene ether) glycol terephthalate, 20.1% by weight of poly(tetramethylene ether) inphthalate, and the poly(alkylene oxide) glycol used to prepare this copolyether ester. had a molecular weight of 2000. The ethylene oxide content of this copolyetherester was zero. The polymer contains 28.2% by weight of short-chain ester units, has a melting point of 124°C and a temperature of 1300 g.
It had a WVTR value of mils/m2/24 hours.

The copolyether ester D forming the hydrophilic layer of the film is 25% by weight of 1.4-butylene terephthalate, and the poly(ethylene oxide) terephthalate whose molecular weight is 1450 for the poly(alkylene oxide) glycol used to produce the copolyether ester. 50% by weight,
and poly(alkylene oxide) glycol has a molecular weight of 2
000 poly(tetramethylene ether) terephthalate. This copolyetherester had a calculated ethylene oxide content of 45.8% by weight and contained 25% by weight of short chain ester units. This polymer had a melting point of 150°C and a WVTR of 17,500 gm/m2/24 hours.

Copolyetherester E forming the hydrophobic layer of the film contains 31% by weight of 1,4-butylene terephthalate, 1
．． It contained 9% by weight of 4-butylene isoterephthalate, 46.5% by weight of terephthalate of a copolyether of ethylene oxide/propylene oxide, and 13.5% by weight of isophthalate of a copolyether of ethylene oxide/propylene oxide. The copoly(alkylene oxide) glycol used to make this copolyetherester was prepared by terminating poly(propylene ether) glycol with 30% by weight ethylene oxide. It had a molecular weight of 2150.

This copolyetherester had a calculated ethylene oxide content of 17% by weight and also contained 40% by weight of short chain ester units. The polymer had a melting point of 155°C and a WVTR of 2240 g"mil/m"/24 hours.

The test water vapor transmission rate (WVTR) used was ASTM E96-6.
6 (No. BW method) at 22°C.

Example 1 Copolyetherester A was fed to a 1.5 inch diameter extruder connected to a melt coalescing block. Copolyetherester B was fed to a 1 inch diameter extruder connected to the same melt coalescing block. Copolyetherester A was heated to 205°C and 2Or
coextruded with pm and also coextruded copolyetherester B with 2
The mixture was heated to 0.05° C. and coextruded at 5 rpm into a connected molten block in an extruder. The coextruded layers were combined in a melt block. Then add a layer of approx.
It passed through a nozzle connected to a combined block having a 14 inch wide nozzle block heated to 0.5°C. The bonded two-component film emerged from the cap with a combined thickness of 1 mil. Copolyetherester A1, the hydrophilic layer, was 0.9 mil (0.0229 mm) and copolyetherester B1, the hydrophobic layer, was 0.1 mil (0.0025 mm) thick. 2 coming out of the mouthpiece
the component film with the hydrophilic layer adjacent to the woven scrim;
It was coated onto a lightweight woven scrim of spunbonded polyethylene terephthalate nonwoven fabric as a substrate.

AS WVTR of two-component film with scrim substrate
Determined in accordance with TM E96-66 (Article BW Law)
;. WVTR value when hydrophilic layer faces water is 3890
g·mil/m”/24 h, and the WVTR value when the hydrophobic layer of the two-component film faces the water is only 1850 g·mil/m”/24 h, resulting in a water vapor separation ratio of 2
．． It was 1.

Example 2 Hydrophobic copolyetherester C (1310g/mil/
The procedure described above in Example 1 was repeated except that the same amount of hydrophobic copolyetherester B (having a WVTR of m2/24 hours) was substituted and extruded under the same conditions. Release paper was used as a substrate in place of the woven scrim and was removed from the two-component film prior to water vapor permeability determination. The coextruded two-component film had a WVTR of 8450 g·mil/m''/24 hours as measured with water in contact with copolyetherester A and water in contact with copolyetherester C during testing. When measured, it was only 4120 g·mil/m2/24 hours.The water vapor separation ratio was 2.
It was 05.

Examples 3-4 The procedure described above in Example 1 was repeated except that Copolyetherester B was replaced by Copolyetherester C for the hydrophobic layer of the two-component film. Also 2
The total thickness of the extruded film of each component structure is 3.
1 mil (Example 3) and 6.5 mil (Example 4). They had layer sections of different thicknesses as shown in Table 1 based on varying the screw speed and linear speed of the equipment. Release paper rather than woven scrim was used as the substrate and was removed prior to determining water vapor permeability.

The total polymer thickness and portions of each of the films described in Table 1 are determined according to ASTM E96-66 (Part BW method).
The water vapor permeability rate (WVTR) as measured by the method was determined by measurement of cross-sectional micrographs.

Table I Table 3. 13 1141047742.34 . 47
36002366 1.5wVTR-g・mil/m
” / 24:00 WVT) 2 (+) - Main tree side facing the water W
VTR (D) - Hydrophobic side facing water The data in Table 1 is based on the water vapor separation ratio (WVTR(1)/W
VTR (D)) is copolyether ester C part 0 (
It shows that the maximum value is reached between ratio = 1.0) and 0.47.

Examples 5-6 In Examples 5 and 6, copolyetherester E was used instead of copolyetherester B, and this was
Example 1 Extruding from an inch extruder at lQrpm
The method described above was repeated. Copolyetherester A was used in Example 5 and copolyetherester D was used in Example 6.

Both had 6% diatomaceous earth by weight. The copolyetheresters were extruded at 2Q rpm from a 1.5 inch diameter extruder in each case. The obtained copolyetheresters A and E (Example 5) were then coated with a two-component film of copolyetheresters D and E (Example 6) on a polyethylene terephthalate film [Mylar (MYLA)].
R@)] was melt-coated onto a substrate. In each example, the total film thickness of the two-component film construction was 0.65 mil and the copolyetherester 8 portion thickness was 0.2. ASTM E96-66 after removal of Mylar substrate
The WVTR measured at 8W and the calculated water vapor separation ratio are shown in the table.

Table 5 6351 4130 1.54 6 81265805 1.40 WVTR-g Mill 7m2/24 hours WVTR (1) = Mother tree side facing water WVTR (D) - Hydrophobic side facing water Example 7 The two-component film structure of Example 1 having a woven scrim substrate was prepared using various textile materials: (a) nylon taffeta, (b)
polyester cotton blend, and (c) Lycra (Ly
cra■) Laminated with spandex fiber by heat. A hydrophobic layer, copolyetherester B, was placed next to the textile material and a flexible layered product was produced in a Verduin calender consisting of a rubber roll placed on a heated roll. In each case, the textile material was placed next to the layer of copolyetherester B and in the nip of the roll for 40 minutes.
By applying tons of force and heating the lower roll to 170°C, the two-component film structure was made 13 feet/ft.
It was fed between the rolls of the calender at a speed of 1 minute. The two-component film structure of the flexible layered product obtained in each case could not be peeled off from the textile material without tearing. The WVTR of the two-component film structure and textile material with the hydrophilic side facing the water is 4705 g.mil 7 m2/24 h for the nylon tack sample, 3711 g.mil 7 m2/24 h for the polyester-cotton blend sample and Lycra. For the spandex sample it was 4772 g.mil/m''/24 hours.

Example 8 The two-component films described in Examples 5 and 6 were
An InLra-roto (InLra-
The nylon tack fabric material was adhesively laminated by conventional laminating equipment, such as a roto coating and laminating machine.

The hydrophobic side of each two-component film was coated with a polyurethane adhesive [Adcote 503] dissolved in methyl ethyl ketone by using a No. 84 gravure roll.
Coated with Al. After coating each hydrophobic layer with adhesive, the two-component film was passed through an oven heated to 82°C to remove the solvent. The woven fabric is unrolled from the roll and placed on the laminating side of the machine, together with the adhesive coated layer, and then sandwiched on a heated roll (121°C) to remove the bicomponent film from the woven fabric on the hydrophobic side. to form a flexible layered product. The line speed of the laminator in each case was 10 feet/min.

The two-component film could not be peeled off from the fabric without tearing, indicating good bond strength between the film and the fabric. For the two-component films described in Examples 5 and 6 above, the WVTR of the flexible products (two-component film and woven fabric) measured with water next to the two-component film was 2551 and 3490 g mil 7 m2, respectively. / It was 24 o'clock.

Example 9 Wood-loving copolyether Estes D 80% by weight and silica [Super-Floss] 20
Concentrate F in the form of pellets consisting of % by weight was prepared by first dry mixing the ingredients and then using a 28 mm twin screw extruder at 215 mm.
Produced by melt mixing using a melt temperature of °C. A physical mixture consisting of 70% by weight Wood Parent Copolyether Aestes A and 30 weight % Parent Concentrate F was fed to a 2.5 inch diameter extruder connected to a melt coalescing block. Hydrophobic copolyether Esthes C was fed to a 1 inch diameter extruder connected to the same melt coalescing block. The blend of Concentrate F and Copolyether Estes A was heated to 205°C and coextruded at a speed of 40 rpm in a 2.5 inch extruder. Also, Copolyether Estes C was heated to 205'O and 22 rpm.
Co-extruded with The layer was then passed through a 60 inch wide film die heated to about 205°C. 2 joined
The component films emerged from the cap with a combined thickness of about 0.5 mil. Concentrates F and Copolyether Esthes A
The layer formed by the blend was 0.45 mil and the layer formed by the Cobolyether Estes was approximately 0.05 mil. The two-component film contained a blend of copolyetherestes elastomers containing silica filler and forming a hydrophilic layer.

Two-component films meet ASTM E96-66 (Part B
According to method W), when water is contacted with a layer (hydrophilic layer) from a blend of Concentrate F and Copolyether Esthes A, a water vapor transmission rate of 5391 g mil/m"/24 hours;
And when water was contacted with the hydrophobic layer of Cobolyether Estes C it had only 4452 g.mil/m''/24 hours.

As a result, the separation ratio was 1.21.

The above examples demonstrate, among other things, that the water vapor permeability and water vapor permeability ratio of a two-component film structure can be adjusted by appropriate selection of polymers, including blends, the thickness of the composite film, and the thickness of the individual layers. ing.

Claims (1)

[Claims] 1. (A) has a thickness of 0.05 to 0.8 mil, and has an AS
400-250 according to TME96-66 (No. BW Law)
A continuous layer of a hydrophobic elastomer having a water vapor transmission rate of 0 g-mil/m^2/24 hours, where the hydrophobic elastomer comprises a large number of repeating long-chain ester units and short-chain esters connected head-to-tail through ester bonds. It is a copolyetherester elastomer having a unit or a mixture of two or more copolyetherester elastomers, and the long chain ester unit is represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (I) and The short chain ester unit is represented by the formula ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (II), where G is an average molecular weight of about 400 to 350
is the divalent group remaining after removal of the terminal hydroxyl group from a poly(alkylene oxide) glycol having 0 and is further present in a copolyetherester or a mixture of two or more copolyetheresters
The amount of ethylene oxide groups introduced by the (alkylene oxide) glycol is not more than about 20% by weight, based on the total weight of the copolyetherester or mixture of two or more copolyetheresters; R has a molecular weight less than 300. D is the divalent group remaining after removing the carboxyl group from the dicarboxylic acid; D is the divalent group remaining after removing the hydroxyl group from the diol having a molecular weight of less than about 250; and D is the divalent group remaining after removing the carboxyl group from the dicarboxylic acid; The mixture of species or more copolyether esters has about 25 to 80 weight percent short chain ester units; (B) has a thickness of 0.3 to 6 mils and meets ASTM 96
A continuous phase of a hydrophilic elastomer having a water vapor transmission rate of at least 3500 g·mil/m^2/24 hours according to Method BW 66 (Part BW Method), where the hydrophilic elastomer has a A copolyetherester elastomer having a large number of long-chain ester units and short-chain ester units having the above-mentioned values, or a mixture of two or more copolyetherester elastomers, which are head-to-tail bonded through ester bonds represented by , where the amount of ethylene oxide groups introduced by the poly(alkylene oxide) glycol into the copolyether ester or the mixture of two or more copolyether esters and the hydrophilic copolyetherester or a mixture of two or more copolyetheresters is about 25% to 68% by weight, based on the total weight of the mixture.
~80% by weight of short chain ester units; and has a separation ratio to water vapor of at least 1.2 as determined by ASTM E96-66 (Method BW) to prevent moisture build-up. A two-component film of a hydrophobic layer and a hydrophilic layer of copolyetherester elastomer joined together to allow differential transport of water vapor. 2. A two-component film according to claim 1, wherein the continuous layer of hydrophilic elastomer comprises a mixture of copolyetheresters. 3. The two-component film according to claim 1, wherein the continuous layer of hydrophilic elastomer contains an inorganic filler. 4. (A) Thickness is 0.05-0.8 mil and AS
400-250 according to TME96-66 (No. BW Law)
A continuous layer of a hydrophobic elastomer having a water vapor transmission rate of 0 g-mil/m^2/24 hours, where the hydrophobic elastomer comprises a large number of repeating long-chain ester units and short-chain esters connected head-to-tail through ester bonds. It is a copolyether ester elastomer having units, the long chain ester unit is represented by the formula ▲ mathematical formula, chemical formula, table, etc. ▼ (I), and the short chain ester unit is represented by the formula ▲ mathematical formula, chemical formula, table, etc. is represented by ▼(II), where G is the average molecular weight of approximately 400 to 350
is the divalent group remaining after removing the terminal hydroxyl group from the poly(alkylene oxide) glycol with 0 and the amount of ethylene oxide groups further introduced by the poly(alkylene oxide) glycol into the copolyether ester is the elastic Approximately 20 based on total body weight
not more than % by weight; R is the divalent group remaining after removing the carboxyl group from a dicarboxylic acid with a molecular weight less than 300; D is the divalent group remaining after removing the hydroxyl group from a diol having a molecular weight less than about 250; and the hydrophobic copolyetherester has a molecular weight of about 25 to 8
(B) has a thickness of 0.3 to 6 mils and meets ASTM 96
A continuous phase of a hydrophilic elastomer having a water vapor transmission rate of at least 3500 g·mil/m^2/24 hours according to Method BW 66 (Part BW Method), where the hydrophilic elastomer has a A copolyetherester elastomer having a large number of long-chain ester units and short-chain ester units head-to-tail bonded through ester bonds and having the above-mentioned values, where poly(alkylene oxide) The amount of ethylene oxide groups introduced by the glycol is about 25-68% by weight based on the total weight of the copolyetherester, and the hydrophilic copolyetherester contains about 25-80% by weight of short chain ester units; and having a separation ratio to water vapor of at least 1.4 as determined by ASTM E 96-66 (Method BW), according to claim 1. A two-component film of a hydrophobic layer and a hydrophilic layer of copolyetherester elastomer joined together to allow differential migration of . 5. Poly(alkylene oxide) for hydrophobic elastomer
5. The two-component film of claim 4, wherein the glycol is poly(tetramethylene oxide) glycol. 6. Poly(alkylene oxide) for hydrophobic elastomer
5. A two-component film according to claim 4, wherein the glycol is a polypropylene oxide glycol terminated with ethylene oxide. 7. Poly(alkylene oxide) for hydrophilic elastomer
5. The two-component film of claim 4, wherein the glycol is poly(ethylene oxide) glycol. 8. At least about 70% of the groups represented by R in formulas (I) and (II) are 1,4-phenylene groups, and at least about 70% of the groups represented by D in formula (II) are 1,4-phenylene groups.
% are 1,4-butylene groups, and the sum of the percentages of R groups that are not 1,4-phenylene groups and D groups that are not 1,4-butylene groups does not exceed 30%.
The two-component film described in Section 1. 9. Copolyether ester of hydrophilic elastomer is 40-6
Claim 4 containing 0% by weight of short chain ester units
The two-component film described in Section 1. 10, copolyether ester of hydrophobic elastic body is 30~
5. A two-component film according to claim 4 containing 60% by weight of short chain ester units. 11. Claim 4, wherein the poly(alkylene oxide) glycol of the hydrophobic elastomer is poly(tetramethylene ether) glycol, and the poly(alkylene oxide) glycol of the hydrophilic elastomer is poly(ethylene oxide) glycol. The two-component film described in Section 1. 12. The two-component film according to claim 4, wherein the hydrophilic layer contains an inorganic filler. 13. The two-component film according to any one of claims 1 to 12, wherein the hydrophobic elastic body is covered with a textile material. 14. (1) a textile material; (2) (A) having a thickness of 0.05 to 0.3 mil;
800-12 according to STME96-66 (No. BW Law)
A continuous layer of a hydrophobic elastomer adhered to said textile material having a water vapor transmission rate of 00 g·mil/m^2/24 hours, wherein said hydrophobic elastomer comprises a number of repeats bonded head-to-tail through ester linkages. It is a copolyether ester elastomer having a long chain ester unit and a short chain ester unit, and the long chain ester unit is represented by the formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (I), and the short chain ester unit is It is represented by the formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (II) where G is the average molecular weight of approximately 400 to 350
is the divalent group remaining after removing the terminal hydroxyl group from the poly(alkylene oxide) glycol with 0 and the amount of ethylene oxide groups further introduced by the poly(alkylene oxide) glycol into the copolyether ester is the elastic Approximately 20 based on total body weight
not more than % by weight; R is the divalent group remaining after removing the carboxyl group from an aromatic dicarboxylic acid having a molecular weight less than 300; D is the divalent group remaining after removing the hydroxyl group from a diol having a molecular weight less than about 250; and the hydrophobic elastomer has about 30 to 60 weight percent short chain ester units; (B) has a thickness of 0.3 to 6 mils and conforms to ASTM 96
- at least 3500 to 20 in accordance with 66 (Article BW Law)
a continuous phase of hydrophilic elastomer adhered to said hydrophobic layer having a water vapor transmission rate of 000 g·mil/m^2/24 hours, where said hydrophilic elastomer has formulas (I) and (II); A copolyetherester elastomer having a large number of long-chain ester units and short-chain ester units having the above-mentioned values, which are head-to-tail bonded through ester bonds represented by The amount of ethylene oxide groups introduced by the oxide) glycol is approximately 25 to 6, based on the total weight of the elastomer.
8% by weight, and the copolyetherester elastomer comprises about 40-60% by weight short chain ester units; a two-component film of a hydrophobic layer and a hydrophilic layer of copolyetherester elastomer bonded together, allowing differential migration of water vapor to prevent moisture buildup, with a separation ratio to water vapor of 6. A flexible layered product comprising: 15. The flexible layered product according to claim 14, wherein the poly(alkylene oxide) glycol of the hydrophilic elastomer is poly(ethylene oxide) glycol. 16. Claim 14, wherein the poly(alkylene oxide) glycol of the hydrophobic elastomer is poly(tetramethylene ether) glycol, and the poly(alkylene oxide) glycol of the hydrophilic elastomer is poly(ethylene oxide) glycol. Flexible layered products as described in Section. 17. At least about 70% of the groups represented by R in formulas (I) and (II) are 1,4-phenylene groups, and at least about 70% of the groups represented by D in formula (II)
0% of the groups are 1,4-butylene groups, and the total percentage of R groups that are not 1,4-phenylene groups and D groups that are not 1,4-butylene groups does not exceed 30%. flexible layered products. 18. The flexible layered product according to claim 14, wherein the hydrophilic elastomer contains an inorganic filler.