阅读说明：本技术 门板用环保柔性亚光聚酯薄膜及其制备方法 (Environment-friendly flexible matte polyester film for door plate and preparation method thereof ) 是由 林树光 刘振 董兴广 冯敏妍 林燕洁 于 2019-12-31 设计创作，主要内容包括：本发明公开了一种门板用环保柔性亚光聚酯薄膜及其制备方法。其中所述门板用环保柔性亚光聚酯薄膜包括芯层、复合于芯层上表面的上表层、及复合于芯层下表面的下表层；所述芯层由结晶型PET均聚物、1,4-环己烷二甲醇与1,4-丁二醇改性的PET共聚物组成。本发明采用特定材料所制得的三层结构的柔性亚光聚酯薄膜,柔韧性好,克服了聚酯薄膜在模压过程中存在局部位置附着牢度不够的问题,同时解决了PVC在吸塑模压过程中,存在棱角位置发白的问题,并且环保良好。(The invention discloses an environment-friendly flexible matte polyester film for a door plate and a preparation method thereof. The environment-friendly flexible matte polyester film for the door plate comprises a core layer, an upper surface layer compounded on the upper surface of the core layer and a lower surface layer compounded on the lower surface of the core layer; the core layer is composed of a crystalline PET homopolymer and a PET copolymer modified by 1, 4-cyclohexanedimethanol and 1, 4-butanediol. The flexible matte polyester film with the three-layer structure, which is prepared from the specific material, has good flexibility, overcomes the problem of insufficient adhesion fastness at local positions in the mould pressing process of the polyester film, solves the problem of whitening of corner positions in the plastic suction mould pressing process of PVC, and is environment-friendly and good.)

1. An environment-friendly flexible matte polyester film for a door plate is characterized by comprising a core layer, an upper surface layer compounded on the upper surface of the core layer and a lower surface layer compounded on the lower surface of the core layer; the core layer is composed of a crystalline PET homopolymer and a PET copolymer modified by 1, 4-cyclohexanedimethanol and 1, 4-butanediol.

2. The environment-friendly flexible matte polyester film for the door panel according to claim 1, wherein the upper surface layer mainly comprises a crystalline PET homopolymer and a crystalline PET copolymer modified by a micron inorganic substance; preferably, the lower surface layer mainly comprises micron inorganic matter, isophthalic acid and 1, 4-butanediol modified crystalline PET copolymer, or mainly comprises crystalline PET homopolymer, micron inorganic matter, isophthalic acid and 1, 4-butanediol modified crystalline PET copolymer.

3. The environment-friendly flexible matte polyester film for the door panel as claimed in claim 2, wherein the mass percentage of the crystalline PET homopolymer and the PET copolymer modified by 1, 4-cyclohexanedimethanol and 1, 4-butanediol in the core layer is 0-50% to 50-100%; preferably, the mass percentage of the crystalline PET homopolymer and the micron inorganic substance modified crystalline PET copolymer in the upper surface layer is 70-80% to 20-30%; preferably, the mass percentage of the crystalline PET homopolymer in the lower surface layer, the micron inorganic matter, the isophthalic acid and the 1, 4-butanediol modified crystalline PET copolymer is 70-80% to 20-30%.

4. The environment-friendly flexible matte polyester film for the door panel according to claim 2, wherein the micron inorganic substance modified crystalline PET copolymer is prepared by the following steps: mixing the micron inorganic substance, terephthalic acid and ethylene glycol according to the mass ratio of 1.0-2.0: 50-70: 30-45, esterification and polycondensation; preferably, the 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer is prepared by the following steps: mixing terephthalic acid, ethylene glycol, 1, 4-cyclohexane glycol and 1, 4-butanediol according to the mass ratio of 50-70:5-15:10-25:15-25, esterifying and polycondensing; preferably, the micron inorganic substance, the isophthalic acid and the 1, 4-butanediol modified PET copolymer are prepared according to the following steps: mixing the micron inorganic substance, terephthalic acid, isophthalic acid, ethylene glycol and 1-4-butanediol according to the mass ratio of 0.2-0.3:20-55:13-40:15-20:15-30, esterifying and polycondensing.

5. The environmentally friendly flexible matte polyester film for door panels as claimed in claim 4, wherein the esterification conditions of the micron inorganic modified crystalline PET copolymer are as follows: the pressure is 0.1-0.15 MPa, the temperature is 255-270 ℃, the reaction is carried out for 100-150 min, and the polycondensation reaction conditions are as follows: the vacuum degree is 45-55 pa, the temperature is 275-285 ℃, and the reaction time is 3-4 h; preferably, the esterification conditions of the 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer are as follows: the pressure is 0.1-0.15 MPa, the temperature is 255-270 ℃, the reaction is carried out for 100-150 min, and the polycondensation reaction conditions are as follows: the vacuum degree is 45-55 pa, the temperature is 275-285 ℃, and the reaction time is 3-4 h; preferably, the esterification conditions of the micron inorganic substance, the isophthalic acid and the 1, 4-butanediol modified PET copolymer are as follows: the pressure is 0.1-0.15 MPa, the temperature is 255-270 ℃, the reaction is carried out for 100-150 min, and the polycondensation reaction conditions are as follows: the vacuum degree is 45-55 pa, the temperature is 275-285 ℃, and the reaction time is 3-4 h.

6. The environmentally friendly flexible matte polyester film for door panels as claimed in any one of claims 1 to 5, wherein the crystalline PET homopolymer has a melting point of 256 to 262 ℃, an intrinsic viscosity of 0.66 to 0.70 dl/g; preferably, the melting point of the micron inorganic substance modified crystalline PET copolymer is 252-262 ℃, and the intrinsic viscosity is 0.66-0.70 dl/g; preferably, the melting point of the 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer is 210-235 ℃, and the intrinsic viscosity is 0.80-0.85 dl/g; preferably, the melting point of the micrometer inorganic substance, isophthalic acid and 1, 4-butanediol modified PET copolymer is 200-235 ℃, and the intrinsic viscosity is 0.8-1.0 dl/g.

7. The environmentally friendly flexible matte polyester film for door panels as claimed in any one of claims 1 to 5, wherein the micro inorganic substance is selected from sodium silicate and SiO₂One or more than two of calcium carbonate and montmorillonite; preferably, the particle size of the micron inorganic substance is 3.5-4.5 μm, and more preferably 3.5-4.0 μm.

8. The environmentally friendly flexible matte polyester film for door panels as claimed in any one of claims 1 to 5, wherein the density of the prepared polyester film is 1.25-1.30 g/m²The thickness is 15-22 μm; the thickness of the upper surface layer and the lower surface layer is 1.5-4.0 μm.

9. A method for preparing the environment-friendly flexible matte polyester film for the door panel as claimed in any one of claims 1 to 8, which is characterized by comprising the following steps:

s1, taking a crystalline PET homopolymer, a 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer as a core layer raw material, and performing pre-crystallization, drying, melting and extrusion;

s2, taking a mixture of a crystalline PET homopolymer and a micron inorganic substance modified crystalline PET copolymer as an upper surface layer raw material, and performing pre-crystallization, drying, melting and extrusion;

s3, taking a micron inorganic substance, isophthalic acid and 1, 4-butanediol modified crystalline PET copolymer as a lower surface layer raw material, or taking a mixture of a crystalline PET homopolymer and the micron inorganic substance, isophthalic acid and 1, 4-butanediol modified crystalline PET copolymer as the lower surface layer raw material, and performing pre-crystallization, drying, melting and extrusion;

and S4, co-extruding and molding the core layer raw material, the upper surface layer raw material and the lower surface layer raw material which are subjected to melt extrusion through a composite die head, respectively compounding the upper surface layer raw material and the lower surface layer raw material on the upper surface and the lower surface of the core layer raw material, quenching to form a casting sheet, preheating the casting sheet, longitudinally stretching to obtain a primary membrane, preheating again, transversely stretching to obtain a base membrane, cooling, cutting, eliminating static electricity and rolling to obtain the composite membrane.

10. The method according to claim 9, wherein the melting temperature of S1-S3 is 260-280 ℃, and the mixture is extruded by a single-screw extruder; preferably, the longitudinal stretching multiple in S4 is 2.5-3.4, and the transverse stretching multiple is 3.4-4.4; preferably, the temperature for rapidly cooling into the cast piece in the step S4 is 15-40 ℃, the preheating temperature is 50-80 ℃, and the temperature for longitudinally stretching is 60-88 ℃; preferably, the temperature for preheating again is 90-100 ℃; the temperature during transverse stretching is 100-110 ℃.

Technical Field

The invention belongs to the technical field of polymer films, and relates to an environment-friendly flexible matte polyester film for a door plate and a preparation method thereof.

Background

The traditional door plate is a baking varnish plate, and the manufacturing process of the baking varnish plate is to use a density plate as a base material, and the surface of the density plate is subjected to high-temperature baking by spraying baking varnish for many times. The novel environment-friendly floor is characterized by bright color, easy modeling, very strong visual effect, very beautiful and fashionable appearance, water resistance, strong anti-pollution capability and easy cleaning. Has the disadvantages of high process level requirement, high rejection rate, high cost, great environmental pollution, elaborate care when in use, fear of colliding with scratches, difficult repair once the damage occurs, and integral replacement

In view of the problems of the traditional baking finish plate, the plastic uptake door plate originates from the west and is gradually popularized, the plastic uptake door plate is also called a mould pressing door plate, a density plate is used as a base material, after pattern engraving and milling by an engraving machine, special glue is finely polished and sprayed, a PVC film is covered on the surface of the plastic uptake door plate and formed by vacuum plastic uptake, the periphery of the door plate after plastic uptake mould pressing is sealed into a whole, secondary edge sealing is not needed, the problems of glue opening and moisture of the door plate after edge sealing for a long time are solved, the plastic uptake door plate is called a non-defective plate, the PVC film is rich in color, the wood grain is vivid and has a three-dimensional effect, the color is pure and bright, the plastic uptake door plate is not cracked, the plastic uptake.

In recent years, on one hand, attention is paid to environment protection, the application of the PVC film in the field of the plastic uptake door panel is correspondingly influenced, on the other hand, in the plastic uptake molding process of the PVC, the corner position is whitened, the attractiveness of the plastic uptake door panel is influenced, for various reasons, the PVC film plastic uptake door panel has various problems, and the common polyester film has the problem of insufficient local position adhesion fastness in the molding process.

Disclosure of Invention

In order to solve the technical problems in the prior art, the invention provides an environment-friendly flexible matte polyester film for a door plate, which is made of a specific material into a three-layer structure, has good flexibility, overcomes the problem that the adhesion fastness of a local position of the polyester film is not enough in the mould pressing process, and simultaneously solves the problem that the corner position of PVC is whitish in the plastic suction mould pressing process.

The environment-friendly flexible matte polyester film for the door plate comprises a core layer, an upper surface layer compounded on the upper surface of the core layer and a lower surface layer compounded on the lower surface of the core layer; the core layer is composed of a crystalline PET homopolymer and a PET copolymer modified by 1, 4-cyclohexanedimethanol and 1, 4-butanediol.

Furthermore, the upper surface layer mainly comprises a crystalline PET homopolymer and a micron inorganic substance modified crystalline PET copolymer; preferably, the lower surface layer mainly comprises crystalline PET copolymer modified by micron inorganic matter and isophthalic acid and 1, 4-butanediol, or mainly comprises crystalline PET homopolymer and micron inorganic matter and isophthalic acid and 1, 4-butanediol modified crystalline PET copolymer.

Furthermore, the mass percentage of the crystalline PET homopolymer, the 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer in the core layer is 0-50%: 50-100%; the mass percentage of the crystalline PET homopolymer and the micron inorganic substance modified crystalline PET copolymer in the upper surface layer is 70-80%: 20-30%; preferably, the mass percentage of the crystalline PET homopolymer in the lower surface layer, the crystalline PET copolymer modified by the micron inorganic matter, the isophthalic acid and the 1, 4-butanediol is 70-80% to 20-30%.

Further, the micron inorganic substance modified crystalline PET copolymer is prepared according to the following steps: mixing the micron inorganic substance, terephthalic acid and ethylene glycol according to the weight ratio of 1.0-2.0%: 50-70%: 30-45% of the raw materials are mixed, esterified and polycondensed; preferably, the 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer is prepared by the following steps: mixing terephthalic acid, ethylene glycol, 1, 4-cyclohexane glycol and 1, 4-butanediol according to the mass ratio of 50-70:5-15:10-25:15-25, esterifying and polycondensing; preferably, the PET copolymer modified by the micron inorganic substance, the isophthalic acid and the 1, 4-butanediol is prepared according to the following steps: mixing the micron inorganic substance, terephthalic acid, isophthalic acid, ethylene glycol and 1-4 butanediol according to the mass ratio of 0.2-0.3:20-55:13-40:15-20:15-30, esterifying and polycondensing.

Furthermore, the esterification conditions of the micron inorganic substance modified crystalline PET copolymer are as follows: the pressure is 0.1-0.15 MPa, the temperature is 255-270 ℃, the reaction is carried out for 100-150 min, and the polycondensation reaction conditions are as follows: the vacuum degree is 45-55 pa, the temperature is 275-285 ℃, and the reaction time is 3-4 h; preferably, the esterification conditions of the PET copolymer modified by 1, 4-cyclohexanedimethanol and 1, 4-butanediol are as follows: the pressure is 0.1-0.15 MPa, the temperature is 255-270 ℃, the reaction is carried out for 100-150 min, and the polycondensation reaction conditions are as follows: the vacuum degree is 45-55 pa, the temperature is 275-285 ℃, and the reaction time is 3-4 h; preferably, the esterification conditions of the micron inorganic substance, the isophthalic acid and the 1, 4-butanediol modified PET copolymer are as follows: the pressure is 0.1-0.15 MPa, the temperature is 255-270 ℃, the reaction is carried out for 100-150 min, and the polycondensation reaction conditions are as follows: the vacuum degree is 45-55 pa, the temperature is 275-285 ℃, and the reaction time is 3-4 h.

Furthermore, the melting point of the crystalline PET homopolymer is 256-262 ℃, and the intrinsic viscosity is 0.66-0.70 dl/g; preferably, the melting point of the micron inorganic substance modified crystalline PET copolymer is 252-262 ℃, and the intrinsic viscosity is 0.66-0.70 dl/g; preferably, the melting point of the 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer is 210-235 ℃, and the intrinsic viscosity is 0.80-0.85 dl/g; preferably, the melting point of the micrometer inorganic substance, isophthalic acid and 1, 4-butanediol modified PET copolymer is 200-235 ℃, and the intrinsic viscosity is 0.8-1.0 dl/g.

Specifically, the micron inorganic matter is selected from sodium silicate and SiO₂One or more than two of calcium carbonate and montmorillonite; preferably, the particle size of the micron inorganic substance is 3.5-4.5 μm, and more preferably 3.5-4.0 μm.

Specifically, the density of the environment-friendly flexible matte film for the door panel is 1.25-1.30 g/m²The thickness is 15-22 μm; the thickness of the upper surface layer and the lower surface layer is 1.5-4.0 μm.

The invention also aims to provide a method for preparing the environment-friendly flexible matte polyester film for the door panel, which comprises the following steps:

s1, taking a crystalline PET homopolymer, a 1, 4-cyclohexanedimethanol and 1, 4-butanediol modified PET copolymer as a core layer raw material, and performing pre-crystallization, drying, melting and extrusion;

s2, taking a mixture of a crystalline PET homopolymer and a micron inorganic substance modified crystalline PET copolymer as an upper surface layer raw material, and performing pre-crystallization, drying, melting and extrusion;

s3, taking a crystalline PET copolymer modified by micron inorganic matters, isophthalic acid and 1, 4-butanediol as a lower surface layer raw material, or taking a mixture of a crystalline PET homopolymer and the crystalline PET copolymer modified by the micron inorganic matters, the isophthalic acid and the 1, 4-butanediol as a lower surface layer raw material, and pre-crystallizing, drying, melting and extruding the mixture;

and S4, co-extruding and molding the core layer raw material, the upper surface layer raw material and the lower surface layer raw material which are subjected to melt extrusion through a composite die head, respectively compounding the upper surface layer raw material and the lower surface layer raw material on the upper surface and the lower surface of the core layer raw material, quenching to form a casting sheet, preheating the casting sheet, longitudinally stretching to obtain a primary membrane, preheating again, transversely stretching to obtain a base membrane, cooling, cutting, eliminating static electricity and rolling to obtain the composite membrane.

Further, the melting temperature of the S1-S3 is 260-280 ℃, and a single-screw extruder is used for extruding; preferably, the longitudinal stretching multiple in S4 is 2.5-3.4, and the transverse stretching multiple is 3.4-4.4; preferably, the temperature for rapidly cooling into the cast sheet in the step S4 is 15-40 ℃; the preheating temperature is 50-80 ℃; the temperature during longitudinal stretching is 60-88 ℃; preferably, the temperature for preheating again is 90-100 ℃; the temperature during transverse stretching is 100-110 ℃.

The invention adopts the technical scheme to achieve the following beneficial effects:

the core layer of the flexible matte polyester film for the door panel is the PET copolymer modified by 1, 4-cyclohexanedimethanol and 1, 4-butanediol, so that the common polyester film does not have flexibility, and the phenomenon of insufficient adhesion fastness cannot occur in the compression molding process after the door panel is coated with a film; because the upper surface layer mainly comprises the crystalline PET homopolymer and the crystalline PET copolymer modified by the micron inorganic substance, the micron inorganic substance ensures that the flexible matte film for the door plate has the effects of scratch resistance and good appearance.

Detailed Description

The present invention will be described in more detail with reference to specific preferred embodiments, but the present invention is not limited to the following embodiments.

The crystalline PET homopolymer used in the present invention may be FG600 produced by instrumented company or polyester chip 5011 produced by three-lane company.

When the invention is used for preparing the micron inorganic substance modified crystal type PET copolymer, the used micron inorganic substance can also use sodium silicate, calcium carbonate and montmorillonite.