KR20150135621A - Foamed sheet and method for preparing foamed sheet - Google Patents

Abstract

Provided is a foam sheet including a foam layer which is produced by a foaming process using a foaming resin composition. The foaming resin composition of the present invention comprises 100 parts by weight of bio resin, and 0.01-20 parts by weight of inorganic foaming agent.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a foam sheet,

And a method for producing the foam sheet and the foam sheet.

A typical foam sheet is manufactured using a resin such as polyvinyl chloride (PVC). However, due to the fact that the raw materials are obtained from crude oil, which is a limited resource, it is expected that problems such as difficulty in supplying raw materials to the future due to depletion of petroleum resources are expected to occur.

In addition, even considering the recent interest in environmental problems, polyvinyl chloride (PVC) -based sheets are liable to discharge harmful substances and burden the environment even when disposing of them.

On the other hand, an ADCA (azodicarbonamide) based blowing agent used in a foam sheet generates reactive substances such as ammonia or cyanuric acid upon foaming, and the reactive material thus generated reacts with the resin again to lower the viscosity of the melt, .

The present invention provides an environmentally friendly foam sheet.

Another embodiment of the present invention provides a method for producing an environmentally friendly foam sheet having excellent processability.

In one embodiment of the present invention, there is provided a foam sheet comprising a foam layer formed by foaming a foamable resin composition comprising 100 parts by weight of a bio-resin and 0.01 to 20 parts by weight of an inorganic foaming agent.

The bio-resin may include a plant-derived bio-resin or a petrochemical-derived biodegradable resin.

The bio-resin may be polylactic acid (PLA); And cellulose, chitin, starch, thermoplastic starch, polyhydroxylalkanoates (PHA), polyhydroxybutyrate valerate (PHBV), polyhydroxyalkanoates butyrate valerate resin, polyvinyl alcohol, polyglycolic acid (PGA), polyolefin, polyethylene terephthalate (PET), thermoplastic polyolefin (TPO), polybutylene succinate (PBS) , Polybutylene terephthalate (PBT), polybutylene adipate terephthalate (PBAT), polybutylene adipate-co-butylene succinate (PBAS) , Polybutylene adipate-co-butylene succinate terephthalate (PBAST), polytrimethylene terephthalate (PTT), polybutylene terephthalate at least one member selected from the group consisting of ate, polycaprolactone, polyamide (PA), polyurethane (PU), poly (ester-amide) A biodegradable resin, and a biodegradable resin.

The inorganic foaming agent may include at least one selected from the group consisting of sodium bicarbonate, ammonium carbonate, ammonium bicarbonate, ammonium nitrite, an azide compound, sodium borohydride, and combinations thereof.

The foamable resin composition may further comprise at least one additive selected from the group consisting of plasticizers, processing aids, fillers, lubricants, crosslinking agents, heat stabilizers, foam stabilizers, and combinations thereof.

Wherein the foamable resin composition comprises 0 to 50 parts by weight of a plasticizer, 1 to 30 parts by weight of a processing aid, 0 to 300 parts by weight of a filler, 0.01 to 10 parts by weight of a lubricant, 0 to 5 parts by weight of a crosslinking agent, 0 to 10 parts by weight of a heat stabilizer, and 0.1 to 5 parts by weight of a foam stabilizer.

The foam sheet may have a thickness of 10 mu m to 3000 mu m.

In another embodiment of the present invention, 100 parts by weight of a plant-derived bio-resin and 0.01 to 20 parts by weight of an inorganic foaming agent are mixed to prepare a foamable resin composition; Forming the foamable resin composition into a sheet; And a step of heating and foaming the sheet to produce a foam sheet.

The step of forming the foamable resin composition into a sheet can be performed by a casting process, a calendering process, or a T-die extrusion process.

The foamable resin composition may be formed into a sol state, then molded into a sheet by a casting process, and then foamed.

First, the bio-resin is prepared in the form of pellets or powder and then mixed with a foaming agent and an additive to prepare a foamable resin composition. After the sheet is molded by a calendering process or a T-die extrusion process, have.

The sheet can be foamed at a temperature range of 100 to 300 캜.

The foam sheet is excellent in workability and is environmentally friendly.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited thereto, and the present invention is only defined by the scope of the following claims.

In one embodiment of the present invention, there is provided a foam sheet comprising a foam layer formed by foaming a foamable resin composition comprising 100 parts by weight of a bio-resin and about 0.01 to about 20 parts by weight of an inorganic foaming agent.

The above-mentioned bio-resin is a concept including both a plant-derived bio-resin produced from biomass as a raw material or a biodegradable resin derived from a petrochemical.

Specifically, the bio-resin may be selected from the group consisting of polylactic acid (PLA), cellulose, chitin, starch, thermoplastic starch (TPS), polyhydroxylalkanoate (PHA) Polyhydroxybutyrate valerate (PHBV) resin, polyvinyl alcohol, polyglycolic acid (PGA), polyolefin, polyethylene terephthalate (PET), thermoplastic polyolefin (TPO) Polybutylene succinate, polybutylene succinate, polybutylene terephthalate (PBT), polybutylene adipate terephthalate (PBAT), polybutylene adipate-co-butylene succinate (PBBA), polybutylene adipate-co-butylene succinate, polybutylene adipate-co-butylene succinate terephthalate (PBAST) (PTT), poly (trimellene terephthalate), polycaprolactone, polyamide (PA), polyurethane (PU), poly (ester-amide), poly (ester-urethane) ≪ / RTI >

In one embodiment, the bio-resin may be a blend resin obtained by mixing polylactic acid and at least one kind of the bio-resin. By using a blend resin, the physical properties of the resin can be improved.

Polylactic acid (PLA) can be divided into crystalline PLA (c-PLA) resin and amorphous PLA (a-PLA) resin. At this time, if only the crystalline PLA resin is used, an amorphous PLA resin may be used because bleeding may occur where the plasticizer flows to the sheet surface. When an amorphous PLA resin is used, there is an advantage that a compatibilizer which is essentially added to prevent bleeding phenomenon is not added. When the amorphous PLA resin is used, the PLA resin can be a 100% amorphous PLA resin, and if necessary, a PLA resin in which crystalline and amorphous coexist can be used.

Examples of the inorganic foaming agent include sodium bicarbonate, ammonium carbonate, ammonium bicarbonate, ammonium nitrite, azide compounds and sodium borohydride.

Particularly, the polylactic acid in the bio-resin has a higher heat or temperature, which promotes hydrolysis, thereby deteriorating physical properties. The foam sheet does not generate a reactive substance by using the inorganic foaming agent even when using polylactic acid This problem of lowering workability can be solved very effectively.

The foamable resin composition may contain the inorganic foaming agent in an amount of about 0.01 to about 20 parts by weight relative to 100 parts by weight of the bio-resin. If the inorganic foaming agent is contained in a small amount below the above content range, the foaming effect can not be attained to a desired level and the porosity of the foam sheet is lowered or the density is increased. If the inorganic foaming agent is contained in an excess amount exceeding the above content range, There is a problem in that the strength of the resin is remarkably reduced and easily broken.

The foamable resin composition may further comprise at least one additive selected from the group consisting of a plasticizer, a processing aid, a filler, a lubricant, a crosslinking agent, a heat stabilizer, a foam stabilizer, a pigment and a combination thereof in addition to the inorganic foaming agent.

The plasticizer is preferably a non-phthalate plasticizer. The plasticizer of the non-phthalate plasticizer is an eco-friendly material and softens the bio-resin to increase thermoplasticity, thereby facilitating molding at high temperatures. As such nonphthalate plasticizer, citric acid, citric acid ester, epoxidized vegetable oil, fatty acid ester, polyethylene glycol, polyethylene propylene glycol, glycerol ester and the like can be used.

The non-phthalate plasticizer may be used in an amount of about 0 to about 50 parts by weight relative to 100 parts by weight of the bio-resin. When the content of the plasticizer is more than about 50 parts by weight, the compatibility with the inert ingredient may deteriorate and the physical properties may be deteriorated, and the plasticizer may be transferred to the surface to deteriorate appearance and physical properties.

The processing aid plays a role of reinforcing the melt strength. Since the bio-resin itself has low melt strength or heat resistance, it is preferable to add processing aid.

As such a processing aid, it is preferable to use an acrylic copolymer, an epoxy copolymer, a urethane copolymer or a polyolefin copolymer. As a result, the melt strength of the bio-resin is compensated to facilitate processing such as car-rendering.

The processing aid may be used in an amount of about 1 to about 30 parts by weight relative to 100 parts by weight of the bio-resin. When the content of the processing aid is less than the above range, the improvement of the melting efficiency and the improvement of the melt strength of the bio-resin is insufficient, and when the amount exceeds the above range, the manufacturing cost increases, And the compatibility with the material may cause degradation of the overall physical properties of each layer.

The filler is generally added for the purpose of changing the physical properties of the bio-resin composition and reducing the cost, and there is no limitation on the kind. For example, calcium carbonate (CaCO ₃ ) is preferably used.

The filler may be used in an amount of about 0 to about 300 parts by weight relative to 100 parts by weight of the bio-resin. If the content of the filler exceeds the above range, excessive use of the filler may cause a change in physical properties.

The lubricant is added in order to prevent the resin from adhering to the calender roll or the press during processing such as car-rendering of the bio-resin.

Such a lubricant is not limited to the use of stearic acid, wax, hydrocarbon, silicone or the like, but in particular, an environmentally friendly higher fatty acid can be used, for example, stearic acid as a saturated fatty acid having a carbon number of 18 can be presented.

The lubricant may be used in an amount of about 0.01 to about 10 parts by weight based on 100 parts by weight of the bio-resin. If the content of the lubricant is less than the above range, the effect of using the lubricant can not be obtained. If the lubricant is used in an amount exceeding the above range, the impact resistance, heat resistance, gloss and the like of the biofabric can be deteriorated.

The crosslinking agent increases the molecular weight through chain extension to improve tensile strength, heat resistance, and the like.

Such a crosslinking agent may be a diisocyanate, an epoxy group copolymer, a hydroxycarboxylic acid compound or the like, but is not limited thereto.

The cross-linking agent may be used in an amount of 0 to about 5 parts by weight relative to 100 parts by weight of the bio-resin. There is a possibility that the flexibility is lowered when the content of the cross-linking agent exceeds the above range and is used in an excessive amount.

The heat stabilizer prevents the degradation of the mechanical properties of the bio-resin during foaming.

The heat stabilizer has no toxicity, is stable at the processing molding temperature, and does not interfere with activity and other resin processability, and has a high compatibility with the resin.

The heat stabilizer may be used in a proportion of 0 to about 10 parts by weight relative to 100 parts by weight of the bio-resin. When the content of the heat stabilizer exceeds the above range, there is a problem of deterioration of physical properties.

The foam stabilizer serves to uniformize the cell size upon foaming.

The foam stabilizer may be used in an amount of about 0.1 to about 5 parts by weight relative to 100 parts by weight of the bio-resin. When the content of the above-mentioned foam stabilizer is less than the above range, there is a problem that the cell size becomes uneven when used in a small amount, and if it exceeds the above range, there is a problem in physical properties.

The thickness of the foam sheet is not particularly limited and can be, for example, about 10 탆 to about 3000 탆, specifically about 10 탆 to about 500 탆.

In another embodiment of the invention,

100 parts by weight of the plant-derived bio-resin and about 0.01 to about 20 parts by weight of an inorganic foaming agent to prepare a foamable resin composition;

Forming the foamable resin composition into a sheet; And

Heating and heating the sheet;

The present invention also provides a method for producing a foam sheet.

The step of forming the foamable resin composition into a sheet can be performed by a casting process, a calendering process, or a T-die extrusion process.

In one embodiment, the foamable resin composition may be used as a sol state and molded into the foam sheet. For example, the volatile solvent may be added to the PLA resin in the form of a sol, then the foaming agent and other additives may be added, the volatile solvent may be removed by a casting process to form a sheet, and then the foaming sheet may be foamed .

In another embodiment, the bio-resin is first prepared in the form of pellets or powder, and then the foaming resin composition is prepared by adding a foaming agent and other additives such as a plasticizer, and then subjected to a calendering process or a T-die extrusion process The foamed sheet may be foamed after sheet molding.

In the step of heating and foaming the sheet, the sheet can be foamed at a temperature range of about 100 to about 300 캜.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, And falls within the scope of the invention.

Claims (12)

100 parts by weight of a biocomposite and 0.01 to 20 parts by weight of an inorganic foaming agent, and a foam layer formed by foaming the foaming resin composition.
The method according to claim 1,
Wherein the bio-resin comprises a plant-derived bio-resin or a petrochemical-derived biodegradable resin
Foam sheet.
The method according to claim 1,
The bio-resin may be polylactic acid (PLA); And cellulose, chitin, starch, thermoplastic starch, polyhydroxylalkanoates (PHA), polyhydroxybutyrate valerate (PHBV), polyhydroxyalkanoates butyrate valerate resin, polyvinyl alcohol, polyglycolic acid (PGA), polyolefin, polyethylene terephthalate (PET), thermoplastic polyolefin (TPO), polybutylene succinate (PBS) , Polybutylene terephthalate (PBT), polybutylene adipate terephthalate (PBAT), polybutylene adipate-co-butylene succinate (PBAS) , Polybutylene adipate-co-butylene succinate terephthalate (PBAST), polytrimethylene terephthalate (PTT), polybutylene terephthalate at least one member selected from the group consisting of ate, polycaprolactone, polyamide (PA), polyurethane (PU), poly (ester-amide) And a biodegradable resin
Foam sheet.
The method according to claim 1,
Wherein the inorganic foaming agent comprises at least one selected from the group consisting of sodium bicarbonate, ammonium carbonate, ammonium bicarbonate, ammonium nitrite, an azide compound, sodium borohydride, and combinations thereof
Foam sheet.
The method according to claim 1,
The foamable resin composition further comprises an additive comprising at least one selected from the group consisting of a plasticizer, a processing aid, a filler, a lubricant, a crosslinking agent, a heat stabilizer, a foam stabilizer,
Foam sheet.
The method according to claim 1,
Wherein the foamable resin composition comprises 0 to 50 parts by weight of a plasticizer, 1 to 30 parts by weight of a processing aid, 0 to 300 parts by weight of a filler, 0.01 to 10 parts by weight of a lubricant, 0 to 5 parts by weight of a crosslinking agent, 0 to 10 parts by weight of a heat stabilizer, and 0.1 to 5 parts by weight of a foam stabilizer
Foam sheet.
The method according to claim 1,
The foam sheet has a thickness of 10 mu m to 3000 mu m
Foam sheet.
100 parts by weight of a plant-derived bio-resin and 0.01 to 20 parts by weight of an inorganic foaming agent to prepare a foamable resin composition;
Forming the foamable resin composition into a sheet; And
Heating and heating the sheet;
≪ / RTI >
9. The method of claim 8,
The step of forming the foamable resin composition into a sheet may be carried out by a casting process, a calendering process or a T-die extrusion process
A method for producing a foamed sheet.
9. The method of claim 8,
The foamable resin composition is prepared into a sol state, then molded into a sheet by a calendering process, and then foamed
A method for producing a foamed sheet.
9. The method of claim 8,
First, the bio-resin is prepared in the form of pellets or powder and then mixed with a foaming agent and an additive to prepare a foamable resin composition. Then, the foamed resin composition is molded by a calendering process or a T-die extrusion process,
A method for producing a foamed sheet.
9. The method of claim 8,
The sheet is foamed at a temperature of 100 to 300 캜
A method for producing a foamed sheet.