JPS62199624A - Production of tough polyvinyl chloride crosslinked body - Google Patents

Abstract

PURPOSE:To obtain a crosslinked body with extremely homogeneous dispersion and tough mechanical properties by kneading polyvinyl chloride together with polyethylene, organic peroxide and crosslinking aid under heating. CONSTITUTION:The objective crosslinked body can be obtained by kneading under heating to 160-180 deg.C of polyvinyl chloride together with (A) polyethylene, (B) an organic peroxide (pref. dicumyl peroxide or 1,3-bis(t-butylperoxy-isopropyl) benzene with a half life at 150 deg.C of (a. 10-11min) and (C) a crosslinking aid (pref. triallyl isocyanurate). The polyvinyl chloride is preferably incorporated, in advance, with a stearic acid-based stabilizer and highly saturated nitrile rubber for discoloration prevention.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a polyvinyl chloride crosslinked product, and in particular to the production of a novel polyvinyl chloride-polyethylene co-crosslinked product that has plasticity and excellent mechanical properties. It is about law.

Conventional technology and its problems In order to plasticize a polar polymer such as polyvinyl chloride (hereinafter abbreviated as PvC), it must be kneaded under heat with a low molecular weight polar polymer such as a phthalate ester. is common. However, the plasticized PvC produced by this method exhibits a stress/strain curve similar to that of a rubber elastomer, and has the disadvantage that the plasticizer migrates when it comes into contact with solvents, oils, etc. In particular, the plasticizer does not transfer from the thin film. The natural bleed phenomenon is also known to be a major drawback.

Means for Solving the Problems The present inventor aims to produce plasticized PVC that is strong and exhibits a stress-strain curve similar to necking-type plastic deformation with a yield point, and that does not have the above-mentioned drawbacks. (hereinafter abbreviated as PE) was considered. An attempt to obtain tough PvC by kneading a non-polar polymer such as PE with a polar polymer such as PvC was completely unthinkable according to conventional common sense; As a result of our continued research on co-crosslinking reactions of polymers, we succeeded in kneading PE into PvC.

The method for producing a tough polyvinyl chloride crosslinked product according to the present invention is as follows:
This method is characterized by kneading polyvinyl chloride with polyethylene, an organic peroxide, and a crosslinking aid under heating.

That is, when kneading 1) E into )) V C, an organic peroxide is added together with a general crosslinking aid and kneaded under heating to cause a co-crosslinking reaction between the two molecules.

A strong PVC crosslinked product can be obtained by the progress of the coating.

The peroxides used in the method of the present invention are dicumyl peroxide, 1,3-bis(t-butylperoxy-
Isoprovil) J Hensen etc. are preferred, but 2.5-
Dimethyl-2,5-di(L-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, each with a longer half-life (1
7 minutes, 100 minutes) peroxides are not excluded.

As understood from the principle described below, the amount of these peroxides added is relatively small, that is, the total amount of resin in the formulation is 100.
The purpose can be achieved by completely reacting even if the amount is 2 parts by weight or less, preferably 1 part by weight or less.

However, when the kneading (processing) temperature is low and the kneading (processing) time is short, the peroxide reacts only partially, so the amount added may be 2 parts by weight or more.

Next, the crosslinking aid used in combination includes all polyfunctional monomers normally used in crosslinking polymeric materials such as polyethylene. In particular, triallyl isocyanurate (TAIC), triallyl cyanurate (TAC), 6-diallylamino-
1,3,6-triazine-2,4-dithiol, 4.6
Polyallyl compounds such as -bis(diallylamino)-1,3,6-)lyazine-2-thiol or hexaallylmelamine are preferred. On the other hand, polyacrylic auxiliary agents having a rapid crosslinking (curing) rate are difficult to handle from the viewpoint of maintaining processability.

These auxiliary agents are added in the amount normally added as a crosslinking auxiliary agent, that is, 3 to 7 parts by weight, preferably about 5 parts by weight, based on 1100 parts by weight of the total resin in the resin compound, to fully exhibit the effect. Ru.

The PvC used in the present invention is a general-purpose polymer that can be expected to be sufficiently effective, and it is not as good as using modified (e.g., copolymerized) PVC or general-purpose plasticizers for the purpose of improving impact resistance and processability. However, as PVC, Cal/j? PVC containing about 0.05 to 2.0% by weight of functional groups such as nyl groups, carboxyl groups, and epoxy groups may be used, or this PvC may be used in combination with general-purpose PvC. On the other hand, PE is soft! (low density)
All qualities of PE, rigid (high density) PE, linear low density PE and ultra-high molecular weight mPE can be used in the present invention.

Next, when kneading PVC, PE, and various additives, it is sufficient to knead them using a hot roll machine, Banbury mixer, etc. at 160 to 1 s ox, and then injection molding or hot press molding. It is preferable to add a stearic acid stabilizer, magnesia, highly saturated nitrile rubber (for example, Z-Ball manufactured by Nippon On Co., Ltd.) to the side in advance in order to prevent coloring due to magnesia and peroxide. The kneading can be done all at once, or step by step, first knead the above compound for PvC, then add the F) E compound to this melt, and while kneading, mix the peroxide of the specified star. A better kneaded product can be obtained by gradually adding .

Furthermore, this kneaded material was heated at 160°C and 30°C using a hot press or the like.
If the co-crosslinked product is formed by heat forming at 180℃ for about 51 minutes, the dispersibility and mechanical properties of the kneaded product can be further improved, and necking type plastic deformation stress with a yield point - A strong (plasticized) PvC exhibiting a strain curve can be obtained.

Function Next, the polymer reaction (co-crosslinking reaction) which forms the basis of the present invention will be explained. In order to make it possible to blend two types of incompatible polymers such as A and B.

Blocks (or grafts) that generally share A and B components
It is necessary to pre-synthesize a third component such as a copolymer and add it during kneading. In the present invention, as an alternative to this, polyvinyl chloride (A) and polyethylene (B) are reacted together with a crosslinking aid (X) in the presence of peroxide in a kneading process under heating, and A-x-n The reaction system was controlled so that co-cured plants such as the following were directly generated during this kneading process. The A-X-B thus produced functions as a dispersion promoter in place of the block (or graft) copolymer, and strengthens the interfacial layer of the two incompatible polymers A and B by the covalent bond via X. Phase separation suppression function (
It is clear that the lid exhibits enhanced mechanical properties.

EXAMPLES Hereinafter, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

Example 1 1” VC (polymerization degree 1450, manufactured by Nihon Ue On Co., Ltd.,
IOIEP) Lug to Magnesia (KIYOWA MAG 150
) 0.1 g, stearic acid stable cutting (Tokyo Fine Chemical Co., Ltd. [RP10+) 0.1 g, and triallyl isocyanurate (TAIC) 0. lL g
At the same time, the mixture was kneaded for about 5 days on a heated roll at 170° C. to prepare a sheet-like kneaded product (1). On the other hand, PE (low-density polyethylene, manufactured by Sumitomo Ihigaku Co., Ltd., Sumirikisen F2+3B
) 5 g on a hot roll at 120°C, TAICo, 2 g
The mixture was kneaded for 5 minutes to prepare a sea I-shaped kneaded product (II). Next, the sheet-like kneaded material (1) was wrapped around a 11J O' loop, and the kneaded material (11) was added thereto and peroxide (manufactured by Nouri Co., Ltd., Barkado) was added while kneading. The kneaded mixture of l) V C and l) E obtained by gradually adding 0.1 g of "Tsuku 214)" and kneading for 5 minutes was placed in a mold with a thickness of Imrn, and hot pressed at 160"C for 30 minutes. A pale brown molded product (Ill) was obtained.

The molded product (Ill) was measured for peel strength, breaking strength, and breaking elongation. Table 1 shows the formulation and physical properties of these PVC-PE co-crosslinked blends.

Comparative Example l A pvc-PE blend was prepared in the same manner as the molded product (Ill) in Example 1, except that no peroxide was added and the lid was removed, and the physical property 11α was measured in the same manner as in Example 1. . The results are shown in Table 1.

Example 2.3 Partially saturated nitrile rubber (hereinafter referred to as
(abbreviated as NBR) (manufactured by Nihon Kami-On Co., Ltd.).

Zet, pol 2010) 1 g was used together as a blending component of PVC and PE. The PvC formulation prepared as above and the PE formulation were mixed at a 2:1 F amount ratio at °C.
Blended and molded into a sheet (Example 2) and blended and molded at a weight ratio of 1:l (Example 3)
)It was created. The product is lighter in color than the sheet of Example 1. The physical properties of each of these were measured. The results are shown in Table 1.

Comparative Example 2.3 PVC-PE blend (Comparative Example 2) as in Examples 2 and 3 except that no peroxide was added.
and (Comparative Example 3) were prepared and their physical properties were measured. The results are also shown in Table 1.

From Table 1 in the margin below, it can be seen that Example 1 exhibits excellent physical properties because the co-crosslinking reaction progresses due to the addition of peroxide, but Comparative Example 1
It turns out that the physical properties are extremely fragile. Also, Example 2. ; Compared to 3, the physical properties of Comparative Examples 2 and 3 are extremely weak.

Example 4.5.6 PVC (Nippon Zeon Co., Ltd. & 1.10IEP) I
Partially saturated NBR (manufactured by Nippon Zeon Co., Ltd., Z
etpol 2010) Ig, magnesia (Kyowa Mag 150) 0.1 g, stearic acid stabilizer (manufactured by Tokyo Fine Chemical Co., Ltd., RPIOI) 0.1 g
and 0.4 g of TAIC were kneaded for about 5 minutes on a heated roll at 160°C to prepare a sheet-like kneaded product (1). On the other hand, ultra-high polymer fjlPE (manufactured by Mitsui Petrochemical Co., Ltd.)
5 g of 185
A sheet material (11) was prepared by kneading the partially saturated NBR0,5B and 2 g of TAICo on a hot roll at .degree. C. for 10 minutes.

Next, the sheet-like material (I) is wrapped around a heated roll at 165°C, and 2.5 g of the sheet-like material (11) is wrapped around it (Example 1↓)
, 5g (Example 5) or log (Example 6), and added peroxide (manufactured by Crude Pharmaceutical Nouri Co., Ltd., Ha9-) while kneading.
A kneaded product of PVC and PE obtained by gradually adding 0.15 g of Kadox 14) was placed in a mold with a thickness of 1 m fTl, and hot pressed at 160°C for 30 minutes to obtain a light brown molded product (Ill). . The breaking strength, breaking elongation, and embrittlement temperature of this molded article (Ill) were measured. Table 2 shows their blending ratios and physical properties.

Comparative Examples 4 and 5.6 Sheet-like products of Comparative Example 4 and t'3.6 were obtained in exactly the same manner as in Example 4, 5.6, except that no peroxide was added. The physical properties of these were measured in the same manner as in Example 4. The blending ratio and physical properties are also shown in Table 2.

As shown in Table 2 in the margin below, the physical properties of Comparative Example 4.5.6 are extremely weak at 6°C, but in Example/i and fit 6°C, the co-crosslinking reaction progresses due to the addition of peroxide. Therefore, the physical properties are significantly improved compared to Comparative Example 4.5.6.

Effects of the Invention As shown in Table 1, even if two sheets of a PVC kneaded product lacking peroxide (no co-crosslinked product is formed) and a PE kneaded product are hot-pressed, the bonded product (comparative example) 1, 2, 3
) has a low peel strength, and the formation of P V C-X-PE!
However, if a peroxide is used in combination to advance the co-crosslinking reaction, the two sheets will form an adhesive with a high peeling strength of 311 (
Examples 1, 2.3) are given.

The resulting PVC-PE blend contains low density PE.
As the number of layers increases, the impact resistance 9, which is a characteristic of PE, increases.
Properties such as surface lubricity and water vapor impermeability are imparted.

Furthermore, as shown in Table 2, the kneaded product containing ultra-high polymer 11PE exhibits the excellent properties of this PE (sheer strength, elongation at break, and low embrittlement temperature).

As described above, the PVC-PE blend obtained by the method of the present invention exhibits an extremely uniform dispersion state and strong mechanical properties, and is expected to be used as a unique new material.

Claims (1)

[Claims] (1) A method for producing a tough crosslinked polyvinyl chloride product, which comprises kneading polyvinyl chloride with polyethylene, an organic peroxide, and a crosslinking aid under heating.