A bending-resistant polyvinyl chloride foamed co-extrusion composite material and a preparation method thereof

Abstract

The application provides a kind of anti-bending type polyvinyl chloride foaming co-extrusion composite material and preparation method, belong to polyvinyl chloride composite material technical field.The composite material of the application is mainly obtained by co-extrusion surface layer, core layer co-extrusion, the surface layer is composed of ASA resin, chlorinated polyether, color masterbatch;The core layer is composed of polyvinyl chloride resin, calcium carbonate, glass fiber mesh cloth, melamine-1,3-bis (4'-aminophenoxy) benzaldehyde resin powder, carboxyl polyester resin, heat stabilizer, foaming agent, lubricant, coupling agent, color masterbatch.The composite material has excellent wear resistance, long span bending strength is higher, is suitable for being used in outdoor weather resistance, wear resistance, long span needs.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of polyvinyl chloride composite materials, and particularly relates to a bending-resistant polyvinyl chloride foaming co-extrusion composite material for long-span and a preparation method. BACKGROUND

[0002] In the current field of composite material floor, there are mainly wood-plastic composite material floor, pure wood material such as wood floor and ordinary shaving reinforced composite floor, etc. Among them, wood floor or ordinary shaving reinforced composite floor cannot be used outdoors due to contact with rainwater, etc. Therefore, wood-plastic composite material is mainly used for outdoor decoration. However, wood-plastic material contains a large amount of wood powder, which has problems of easy mold degradation and decay when used outdoors. The all-plastic composite material without wood powder can solve the defects of easy mold degradation of traditional wood-plastic composite material, but it is difficult to promote due to problems of too large density, too heavy unit mass and too high cost. The foaming process can achieve the purposes of reducing the density of all-plastic composite material, reducing the unit mass and reducing the use cost of plastic, but the foaming process reduces the weight while causing the product to be difficult to burn and the mechanical bending strength to decrease due to the existence of bubbles in the plastic.

[0003] Compared with polystyrene, PE, PP and other plastics, polyvinyl chloride has the advantages of moderate cost and difficult to burn due to high chlorine content. In recent years, the research and market promotion of foamed polyvinyl chloride composite material are relatively fast. However, the bending strength performance of foamed polyvinyl chloride composite material is insufficient, especially when used for long-span (such as span of 350 mm and above), the middle part is easy to deform, and it cannot be used in floor fields with load-bearing requirements and high requirements for bending resistance, especially in fields with a span of more than 350 mm. At the same time, when the foamed polyvinyl chloride composite material is used as floor, it is mainly used in outdoor environment, and it also has high requirements for flame retardance, weather resistance and surface wear resistance. How to obtain a product that meets the comprehensive requirements through the combination of surface layer and core layer is a difficulty. SUMMARY

[0004] In view of the above problems, the application provides a bending-resistant polyvinyl chloride foaming co-extrusion composite material and a preparation method. The composite material has excellent wear resistance and high long-span bending strength, and is suitable for outdoor weather resistance, wear resistance and long-span requirements.

[0005] One of the purposes of the application is to provide a bending-resistant polyvinyl chloride foaming co-extrusion composite material.

[0006] The second purpose of the application is to provide a preparation method of the bending-resistant polyvinyl chloride foaming co-extrusion composite material.

[0007] In order to achieve the above purposes of the application, the following technical solutions are adopted:

[0008] In a first aspect, the present application provides a bending-resistant polyvinyl chloride foamed co-extrusion composite material, which comprises a surface layer and a core layer co-extruded; the mass ratio of the raw materials of the surface layer to the core layer is 0.5-0.8:10; and the core layer further comprises a reinforcing layer formed by a continuous glass fiber mesh.

[0009] The raw materials for preparing the surface layer comprise the following components in parts by weight: ASA resin 70-80 parts, chlorinated polyether 20-30 parts, and ASA color master batch 0.3-0.8 parts.

[0010] The raw materials for preparing the core layer comprise the following components in parts by weight: polyvinyl chloride resin 65-80 parts, modified calcium carbonate 20-25 parts, heat stabilizer 3-5 parts, lubricant 0.4-0.6 parts, coupling agent 0.8-1.0 parts, foaming agent 0.7-1.1 parts, modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin 10-13 parts, carboxyl polyester resin 3-4 parts, and PVC color master batch 0.1-0.3 parts.

[0011] The glass fiber mesh is a glass fiber mesh treated with a methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive.

[0012] The modified calcium carbonate is calcium carbonate modified with a methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive.

[0013] The following will be described in detail:

[0014] Surface layer:

[0015] The typical but non-limiting weight fraction of the ASA resin is, for example, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80 parts.

[0016] The chlorinated polyether can be selected from the product of model 4023 of the U.S. Liquid Nitrogen Processing Company, injection molding grade, particle size, 50-60 mesh.

[0017] The typical but non-limiting weight fraction of the chlorinated polyether is, for example, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 parts.

[0018] The ASA color master batch includes ASA color master batches of conventional colors such as red, yellow, and glaze color.

[0019] The typical but non-limiting weight fraction of the ASA color master batch is, for example, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8 parts.

[0020] Core layer:

[0021] The methyl etherified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin adhesive was prepared by the following method:

[0022] (1) Add 37% (mass fraction) formaldehyde aqueous solution and methanol into the reactor, start stirring and stir evenly, then use 10-15% (mass fraction) sodium hydroxide aqueous solution to adjust the pH value of the system to 8.0-9.0, then add melamine and 1,3-bis(4'-aminophenoxy)benzene, and heat to 65-70°C for insulation polymerization reaction; the molar ratio of the raw materials is melamine: 1,3-bis(4'-aminophenoxy)benzene: formaldehyde (pure formaldehyde): methanol = 1: 0.3-0.4: 7.5-8.8: 2.5-3.0;

[0023] (2) After the reaction system has no insoluble matter and becomes homogeneous, cool it to 40-50°C, add concentrated sulfuric acid to adjust the pH value to 3.0-4.0, and continue the polymerization reaction at this temperature;

[0024] (3) Sampling and testing: when the viscosity of the system is 120-140 mPa.s, add 10-15% (mass fraction) sodium hydroxide aqueous solution to adjust the pH value of the system to 9.0-10.0, increase the temperature and perform reduced pressure distillation, with the vacuum degree controlled at -0.096 to -0.098 MPa and the distillation temperature at 90-95°C;

[0025] (4) Sampling and testing the volatile content of the reactants in step (3). When the volatile content is 30-35%, a methylated melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin adhesive is obtained.

[0026] The modified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin was prepared by the following method:

[0027] (1) Add 37% (mass fraction) formaldehyde aqueous solution and methanol into the reactor, start stirring and stir evenly, then use 10-15% (mass fraction) sodium hydroxide aqueous solution to adjust the pH value of the system to 8.0-9.0, then add melamine and 1,3-bis(4'-aminophenoxy)benzene, and heat to 65-70°C for heat preservation polymerization reaction; the molar ratio of raw materials is melamine: 1,3-bis(4'-aminophenoxy)benzene: formaldehyde: methanol = 1: 0.3-0.4: 7.5-8.8: 2.5-3.0;

[0028] (2) After the reaction system has no insoluble matter and becomes homogeneous, cool it to 40-50°C, add concentrated sulfuric acid to adjust the pH value to 3.0-4.0, and continue the polymerization reaction at this temperature;

[0029] (3) Sampling detection, when the viscosity of the system is 120-140 mPa.s, add 10-15% (mass fraction) of sodium hydroxide solution to adjust the pH value of the system to 9.0-10.0, heat and perform vacuum distillation, the vacuum degree is controlled at -0.096 to -0.098 Mpa, and the distillation temperature is 90-95℃;

[0030] (4) Sampling detection of the volatile content of the reactant in step (3), when the volatile content is 7-10%, remove the vacuum system, add hexamethylol melamine powder, mix uniformly after stirring, and then discharge the material and place it in a vacuum oven for drying treatment, the oven temperature is 85-90℃, the vacuum degree is -0.098 to -0.099 Mpa, and when the volatile content is less than 2%, take out the material and crush it into 60-80 mesh powder to obtain modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder, wherein the molar amount of hexamethylol melamine is 0.1-0.12 times the molar amount of melamine.

[0031] The polyvinyl chloride resin can use the product of model WH900 of Wanhua Chemical Group Co., Ltd., with a K value of 64.

[0032] The typical but non-limiting weight fraction of the polyvinyl chloride resin is, for example, 65, 66, 68, 70, 72, 74, 75, 76, 77, 80 parts.

[0033] The calcium carbonate uses a nano active calcium carbonate special for plastics, with a particle size of 200-300 nm.

[0034] The typical but non-limiting weight fraction of the modified calcium carbonate is, for example, 20, 21, 22, 23, 24, 25 parts.

[0035] The heat stabilizer is a composite of calcium stearate and zinc stearate, with a mass ratio of 2:1-1.3.

[0036] The typical but non-limiting weight fraction of the heat stabilizer is, for example, 3, 4, 5 parts.

[0037] The lubricant is stearic acid or hexadecanoic acid.

[0038] The typical but non-limiting weight fraction of the lubricant is, for example, 0.4, 0.5, 0.6 parts.

[0039] The coupling agent is silane coupling agent JH-M902 or silane coupling agent KH-540.

[0040] The typical but non-limiting weight fraction of the coupling agent is, for example, 0.8, 0.9, 1.0 parts.

[0041] The foaming agent is azodicarbonamide.

[0042] The foaming agent is typically but not limitatively in a weight fraction of, for example, 0.7, 0.8, 0.9, 1.0, 1.1 parts.

[0043] The modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin is typically but not limitatively in a weight fraction of, for example, 10, 11, 12, 13 parts.

[0044] The carboxyl polyester resin has an acid value of 25-29 mgKOH / g, and can be selected from the GH-3305 product of Zhejiang Guanghua Science and Technology Co., Ltd.

[0045] The carboxyl polyester resin is typically but not limitatively in a weight fraction of, for example, 3, 3.5, 4 parts.

[0046] The PVC color masterbatch includes PVC color masterbatch of conventional colors such as red, yellow, glaze, etc.

[0047] The PVC color masterbatch is typically but not limitatively in a weight fraction of, for example, 0.1, 0.2, 0.3 parts.

[0048] The reinforcing layer is:

[0049] The glass fiber mesh cloth has a mesh size of 5 mm x 5 mm and a weight of 130 g / m 2 .

[0050] The methyl etherified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is as described above.

[0051] In a second aspect, the present application provides a preparation method of the above-mentioned anti-bending type PVC foaming co-extrusion composite material, comprising the following steps:

[0052] (1) The formula amount of ASA resin, chlorinated polyether, ASA color masterbatch is mixed uniformly at room temperature, and then melt-extruded and granulated through a double-screw extruder to obtain a surface layer granular material for standby use;

[0053] (2) The formula amount of PVC resin, methyl etherified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive modified calcium carbonate, heat stabilizer, lubricant, coupling agent, modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin, carboxyl polyester resin, foaming agent, PVC color masterbatch is first mixed uniformly at room temperature, and then crushed to a particle size of 70-100 meshes through a high-speed crusher to prepare a core layer premix for standby use;

[0054] (3) According to the mass ratio, the surface layer granular material and the core layer premix are taken, the core layer premix and the surface layer granular material are respectively melted through different double screw extruders, and then are respectively introduced into the core layer cavity and the surface layer cavity of a co-extrusion die, wherein the glass fiber mesh cloth treated by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is fixedly placed at the middle 1 / 2 of the core layer cavity, the core layer melt fills the core layer cavity and is fully combined with the glass fiber mesh cloth, the foaming and the surface layer co-extrusion molding are completed, and then cooling molding, surface layer surface embossing treatment and fixed length cutting are performed to obtain the bending-resistant polyvinyl chloride foaming co-extrusion composite material.

[0055] In some embodiments, in step (1), the barrel temperature of the double screw extruder is 240-250°C, and the screw rotation speed is 150-200 rpm.

[0056] In some embodiments, in step (2), the preparation method of the calcium carbonate modified by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive comprises:

[0057] The methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive (solid content 30-35%) diluted with water is sprayed on the surface of the calcium carbonate by using an automatic sprayer, the mass ratio of the adhesive (after water dilution) to the calcium carbonate is 3-5:100, the calcium carbonate is continuously stirred during the spraying process to make the spraying uniform, after the spraying is completed, the calcium carbonate is fully mixed in a mixing machine for 10-15 min, and then is subjected to vacuum drying treatment to obtain the modified calcium carbonate with a volatile content of less than 1%.

[0058] In some embodiments, in step (3), the preparation method of the glass fiber mesh cloth treated by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive comprises:

[0059] The glass fiber mesh cloth is soaked in the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive for 20-30 s, is hung vertically and is air dried at room temperature until no liquid drops are dropped, is hung in an oven or a drying room for pre-curing treatment by using hot air, the temperature of the oven or the drying room is 80-85°C, and the time is 10-15 min, and then is cooled to room temperature.

[0060] In some embodiments, in step (3), the conditions for the core layer extrusion molding are as follows: the barrel temperature is 200-205°C, and the screw rotation speed is 10-20 rpm.

[0061] The conditions for the surface layer extrusion molding are as follows: the barrel temperature is 220-230°C, and the screw rotation speed is 10-20 rpm.

[0062] Beneficial effects:

[0063] The composite material of the present application is mainly obtained by co-extrusion of the surface layer and the core layer, the surface layer is composed of ASA resin, chlorinated polyether, color masterbatch; the core layer is composed of polyvinyl chloride resin, calcium carbonate, glass fiber mesh cloth, melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder, carboxyl polyester resin, heat stabilizer, foaming agent, lubricant, coupling agent, color masterbatch. Among them, the specific required glass fiber mesh cloth is subjected to pre-dip coating and sizing treatment with methyl etherified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive, then the modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder and the specific carboxyl polyester resin are used in the foaming process of the polyvinyl chloride resin to participate in crosslinking and curing, the six-functionality of hexamethylol melamine is introduced into the modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin, which greatly improves the crosslinking density, hardness and bending strength of the foamed polyvinyl chloride composite material, and also improves the high temperature deformation resistance of the core layer, and the specific carboxyl polyester resin is used to adjust the mechanical properties of the composite material after foaming and molding. At the same time, the simultaneous use of the methyl etherified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive composition and the modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin realizes the co-curing of the melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin on the surface of the glass fiber mesh cloth with the modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin and the carboxyl polyester resin, which not only increases the bonding ability of the glass fiber mesh cloth and the polyvinyl chloride foaming resin material layer, but also greatly improves the bending resistance and flame retardance brought by the glass fiber mesh cloth introduced into the core layer, which can greatly improve the bending strength without obvious weight increase, and is suitable for use in long-span wood-plastic floor field. At the same time, the composite material of the surface layer using chlorinated polyether and ASA resin, the introduction of specific amount and type of chlorinated polyether improves the wear resistance, flame retardance and weather resistance of the surface layer material.

[0064] The present application has been described in detail in the foregoing, but the above-described embodiments are merely illustrative in nature and are not intended to limit the present application. Furthermore, the present text is not limited by any theory described in the foregoing prior art or summary of the invention or in the following examples. DETAILED DESCRIPTION

[0065] The present application will be further described in conjunction with the examples. It should be noted that the following examples are provided only for illustrative purposes and do not constitute a limitation on the scope of the present application.

[0066] The raw materials, reagents, methods, etc. used in the examples are conventional raw materials, reagents, methods in the art, unless otherwise specified.

[0067] The model numbers, manufacturers / providers of the raw materials used in the examples are as follows:

[0068] ASA resin, model HM-957, injection molding grade, Qingdao Zhongxin Huamei Plastic Co., Ltd.;

[0069] ASA color masterbatch and PVC color masterbatch are both from Qingdao Zhongxin Huamei Plastic Co., Ltd.;

[0070] Chlorinated polyether, model 4023, injection molding grade, particle size, 50-60 mesh, U.S. Liquid Nitrogen Processing Company;

[0071] Glass fiber mesh, mesh 5mm x 5mm, grammage 130g / m 2 , Anhui Tianfu New Material Co., Ltd.;

[0072] Carboxyl polyester resin, model GH-3305, acid value 25-29 mgKOH / g, purchased from Zhejiang Guanghua Science and Technology Co., Ltd.;

[0073] Calcium carbonate uses special nano active calcium carbonate for plastics, model SPSL-2, particle size 200-300 nm, Jiangxi Huaming Nano Calcium Carbonate Co., Ltd.;

[0074] The others are conventional raw materials.

[0075] Determination of volatile matter content and solid content: take 10g of sample, put it into a beaker, then put the beaker into a forced air oven for 130℃ / 30min drying treatment, take it out and cool to room temperature, weigh again, the reduced weight is the volatile matter, and the volatile matter content is: Solid content is 100%-volatile matter content.

[0076] Preparation of methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive:

[0077] (1) Add 37% (mass fraction) formaldehyde aqueous solution (containing formaldehyde 8 mol), 3 mol methanol into the reaction kettle, start stirring and stir uniformly, then use 12% (mass fraction) sodium hydroxide aqueous solution to adjust the pH value of the system to 8.5, then add 1 mol melamine and 0.3 mol 1,3-bis(4'-aminophenoxy) benzene, and heat to 70℃, and carry out heat preservation polymerization reaction;

[0078] (2) After the reaction system becomes homogeneous without insoluble matter, cool to 40℃, add concentrated sulfuric acid to adjust the pH value to 3.5, and continue the heat preservation polymerization reaction;

[0079] (3) Sampling and testing: when the viscosity of the system is 120-140 mPa.s, add 12% sodium hydroxide aqueous solution again to adjust the pH value of the system to 9.5, increase the temperature and perform reduced pressure distillation, with a vacuum degree of -0.098 MPa and a distillation temperature of 95°C;

[0080] (4) Sampling and testing the volatile content of the reactants in step (3). When the volatile content is 32%, a methyl etherified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin adhesive is obtained and set aside.

[0081] Preparation Example 2 Preparation of modified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin powder:

[0082] (1)-(3) are the same as those in Preparation Example 1;

[0083] (4) Sampling and testing the volatile content of the reactants in step (3). When the volatile content is 9%, release the vacuum system, add 0.1 mol of hexahydroxymethyl melamine powder, stir and mix evenly, release the material, and place it in a vacuum oven for drying. The oven temperature is 90°C and the vacuum degree is -0.099 MPa. When the volatile content is less than 2%, take out the material and crush it into 60-80 mesh powder to obtain modified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin powder.

[0084] Preparation Example 3 Preparation of calcium carbonate modified with methyl etherified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin adhesive:

[0085] An automatic sprayer is used to spray the methylated melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin adhesive (solid content 30%) diluted with water on the surface of calcium carbonate. The mass ratio of the adhesive to calcium carbonate is 4:100. The calcium carbonate is continuously stirred during the spraying process to ensure uniform spraying. After the spraying is completed, it is fully mixed in a mixer for 10 minutes and then vacuum dried to obtain a modified calcium carbonate with a volatile matter of less than 1%.

[0086] Preparation Example 4 Preparation of glass fiber mesh treated with methyl etherified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin adhesive:

[0087] The glass fiber mesh was soaked in methyl etherified melamine-1,3-bis(4'-aminophenoxy)benzaldehyde resin adhesive for 30 seconds, hung vertically to dry at room temperature until no liquid dripped, and hung in an oven for pre-curing treatment at 85°C for 10 minutes, and then cooled to room temperature.

[0088] Example 1

[0089] A bending-resistant polyvinyl chloride foaming co-extrusion composite material, comprising a surface layer and a core layer co-extruded; the mass ratio of the raw materials of the surface layer and the core layer is 0.65:10; a reinforcing layer formed by a glass fiber mesh treated by a methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is further arranged in the middle of the core layer;

[0090] The raw materials for preparing the surface layer comprise the following components in parts by weight:

[0091] ASA resin 70 parts, chlorinated polyether 30 parts, ASA color master batch 0.3 parts;

[0092] The raw materials for preparing the core layer comprise the following components in parts by weight:

[0093] Polyvinyl chloride resin 75 parts, calcium carbonate modified by a methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive 20 parts, heat stabilizer (calcium stearate and zinc stearate with a mass ratio of 2:1) 4 parts, lubricant stearic acid 0.5 parts, silane coupling agent JH-M902 1.0 parts, foaming agent azodicarbonamide 1 part, modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin 10 parts, carboxyl polyester resin 3 parts, PVC color master batch 0.1 parts.

[0094] A method for preparing the above-mentioned composite material, comprising the following steps:

[0095] (1) Mix the formula amount of ASA resin, chlorinated polyether, and ASA color master batch at room temperature until they are uniformly mixed, then melt-extrude and pelletize them through a double-screw extruder, the barrel temperature of the double-screw extruder is 250°C, and the screw rotation speed is 200 rpm, to obtain surface layer granules, which are ready for use;

[0096] (2) Mix the formula amount of polyvinyl chloride resin, calcium carbonate modified by a methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive, heat stabilizer, lubricant, coupling agent, modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin, carboxyl polyester resin, foaming agent, and PVC color master batch at room temperature until they are uniformly mixed, then crush them through a high-speed crusher to a particle size of 70-100 mesh to prepare core layer premix, which is ready for use;

[0097] (3) According to the mass ratio, the surface layer granular material and the core layer premix are taken, the core layer premix and the surface layer granular material are respectively melted through different double screw extruders, and then are respectively introduced into the core layer cavity and the surface layer cavity of a co-extrusion die, wherein the glass fiber mesh cloth treated by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is fixedly placed at the middle 1 / 2 of the core layer cavity, the core layer melt fills the core layer cavity and is fully combined with the glass fiber mesh cloth, the foaming and the surface layer co-extrusion molding are completed, and then the anti-bending polyvinyl chloride foaming co-extrusion composite material is obtained through the cooling molding, the surface layer surface embossing treatment and the fixed length cutting; the core layer extrusion molding conditions are that the cylinder temperature is 200 DEG C and the screw rotation speed is 10 rpm; the surface layer extrusion molding conditions are that the cylinder temperature is 220 DEG C and the screw rotation speed is 10 rpm.

[0098] Example 2

[0099] An anti-bending polyvinyl chloride foaming co-extrusion composite material, comprising a surface layer and a core layer which are co-extrusion molded; the raw material mass ratio of the surface layer to the core layer is 0.6:10; the core layer further comprises a reinforcing layer formed by the glass fiber mesh cloth treated by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive in the middle part of the core layer;

[0100] The raw material for preparing the surface layer comprises the following components in parts by weight:

[0101] ASA resin 80 parts, chlorinated polyether 20 parts, ASA color master batch 0.8 part;

[0102] The raw material for preparing the core layer comprises the following components in parts by weight:

[0103] Polyvinyl chloride resin 70 parts, calcium carbonate modified by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive 23 parts, heat stabilizer (calcium stearate and zinc stearate with a mass ratio of 2:1) 5 parts, lubricant stearic acid 0.4 part, silane coupling agent KH-540 0.8 part, foaming agent azodicarbonamide 0.8 part, modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin 12 parts, carboxyl polyester resin 4 parts, PVC color master batch 0.3 part.

[0104] The preparation method is the same as that in Example 1.

[0105] Example 3

[0106] An anti-bending polyvinyl chloride foaming co-extrusion composite material, comprising a surface layer and a core layer which are co-extrusion molded; the raw material mass ratio of the surface layer to the core layer is 0.7:10; the core layer further comprises a reinforcing layer formed by the glass fiber mesh cloth treated by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive in the middle part of the core layer;

[0107] The raw materials for preparing the surface layer include the following components by weight:

[0108] ASA resin 75 parts, chlorinated polyether 25 parts, ASA color master batch 0.5 part;

[0109] The raw materials for preparing the core layer include the following components by weight:

[0110] Polyvinyl chloride resin 65 parts, calcium carbonate modified by melinite-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive 25 parts, heat stabilizer (calcium stearate and zinc stearate with a mass ratio of 2:1) 4 parts, lubricant palmitic acid 0.5 part, silane coupling agent KH-540 0.9 part, foaming agent azodicarbonamide 0.7 part, modified melinite-1,3-bis(4'-aminophenoxy) benzaldehyde resin 12 parts, carboxyl polyester resin 3 parts, PVC color master batch 0.2 part.

[0111] The preparation method is the same as that of Example 1.

[0112] Example 4

[0113] A bending-resistant polyvinyl chloride foaming co-extrusion composite material, comprising a surface layer and a core layer co-extruded; the mass ratio of the raw materials of the surface layer to the core layer is 0.55:10; the core layer further comprises a reinforcing layer formed by a glass fiber mesh treated by a melinite-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive in the middle part;

[0114] The raw materials for preparing the surface layer include the following components by weight:

[0115] ASA resin 77 parts, chlorinated polyether 23 parts, ASA color master batch 0.6 part;

[0116] The raw materials for preparing the core layer include the following components by weight:

[0117] Polyvinyl chloride resin 80 parts, calcium carbonate modified by melinite-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive 20 parts, heat stabilizer (calcium stearate and zinc stearate with a mass ratio of 2:1) 5 parts, lubricant palmitic acid 0.5 part, silane coupling agent JH-M902 1.0 part, foaming agent azodicarbonamide 0.9 part, modified melinite-1,3-bis(4'-aminophenoxy) benzaldehyde resin 10 parts, carboxyl polyester resin 4 parts, PVC color master batch 0.1 part.

[0118] The preparation method is the same as that of Example 1.

[0119] Comparative Example 1

[0120] Other than Example 1, the difference is that the core layer does not use modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder, carboxyl polyester resin and glass fiber mesh reinforcement layer, only uses polyvinyl chloride resin and other auxiliary ingredients.

[0121] Comparative Example 2

[0122] Other than Example 1, the difference is that the core layer does not use modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder.

[0123] Comparative Example 3

[0124] Other than Example 1, the difference is that the core layer does not use glass fiber mesh reinforcement layer.

[0125] Comparative Example 4

[0126] Other than Example 1, the difference is that the glass fiber mesh in the core layer is not treated with methylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive.

[0127] Comparative Example 5

[0128] Other than Example 1, the difference is that the core layer uses ordinary heavy calcium carbonate with a particle size of 800 mesh, and the calcium carbonate used is not modified with methylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive.

[0129] Comparative Example 6

[0130] Other than Example 1, the difference is that the core layer does not use carboxyl polyester resin.

[0131] Comparative Example 7

[0132] Other than Example 1, the difference is that the surface layer does not use chlorinated polyether resin, only ASA resin is used.

[0133] Performance testing:

[0134] The long-span bending strength and wear resistance are tested according to the standard of GB / T 29418-2023, among which the bending strength is tested according to part 5.3 (span length 400mm, three-point bending), and the wear resistance is tested according to part 5.13.1 (load weight: 1000g);

[0135] The weather resistance test is carried out according to GB / T 29365-2012, and the exposure condition is carried out according to condition 1 parameter in part 6.2.2, and the test is continuously completed for 10 cycles, a total of 120h.

[0136] The temperature difference resistance performance test is performed according to the following method, that is, (40±2) °C, 3h→(-25±2) °C, 4h→(25±2) °C, 3h, 10h is one cycle, and 30 cycles are continuously performed according to the above temperature difference cycle, and then the appearance crack of the plate is observed.

[0137] The boiling water resistance test method is performed according to the 4.52 part of GB / T-17657-2022 standard.

[0138] Table 1 Performance comparison table of plates of examples and each comparative example

[0139]

[0140] As can be seen from Table 1, the plate of the foamed polyvinyl chloride composite material (Examples 1-4) prepared by using the specific formula and process has a long-span bending strength of 400mm of 63Mp or more, and the surface wear resistance is 195mg / 1000r or less. In terms of weather resistance, after 10 cycles of weather resistance performance test, the surface layer and the core layer are unchanged, especially the surface layer material, which is exposed to the xenon lamp light source, has no apparent change, indicating that the weather resistance is excellent. In terms of temperature difference resistance, after 30 cycles of repeated test in different temperature environments, the interface between the surface layer, the core layer and the glass fiber cloth of the foamed polyvinyl chloride composite material has no crack, indicating that the bonding force and the adhesion are relatively good, and in terms of water resistance, the surface layer and the core layer are unchanged after boiling in water for 2h.

[0141] The comparative example 1 does not use the high-temperature-curable modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder prepared by the present application, the carboxyl polyester resin, and the glass fiber mesh as the reinforcing layer, and only uses the polyvinyl chloride resin and other auxiliary components, which is basically a common polyvinyl chloride core layer foaming composite product. After co-extrusion forming with the surface layer, the bending strength is significantly reduced, and the bending strength at a span of 400 mm can only reach 35.7 Mpa, which is much lower than the bending strength of the product of the present application and cannot be used in long-span fields; the comparative example 2 does not use the modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder, and the carboxyl polyester resin cannot be cured by itself, resulting in no curable components in the core layer composition. Not only is the bending strength significantly reduced, but the bending strength at a span of 400 mm is reduced to 46.9 Mpa, and the core layer lacks the high-temperature curing effect of the modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder, and the interfacial bonding force with the reinforcing layer glass fiber mesh also appears to be slightly reduced; the comparative example 3 does not use the reinforcing layer glass fiber mesh, resulting in a certain degree of decrease in the bending strength, which shows that the glass fiber mesh treated with the adhesive used in the present application is co-cured with the core layer resin, which improves the bending strength; the glass fiber mesh used in the comparative example 4 is not treated with the adhesive, resulting in no resin on the surface of the glass fiber cloth participating in the curing and crosslinking of the core layer resin, resulting in a slight decrease in strength, and in terms of temperature difference resistance performance, the interfacial bonding force between the core layer and the glass fiber mesh also appears to be extremely slightly reduced, resulting in extremely slight cracks; the comparative example 5 uses a commercially available ordinary heavy calcium carbonate and does not use the adhesive for pretreatment, and the compatibility with the core layer system is general, resulting in a decrease in the bending strength, and the core layer has extremely slight loosening changes after boiling in water for 2 h; the comparative example 6 does not use the specific carboxyl polyester resin for adjusting the curing toughness and mechanical properties of the present application, resulting in excessive rigidity and cohesion of the cured core layer, and the core layer may have extremely slight cracks and other defects after temperature difference resistance test; the comparative example 7 only uses the ASA resin as the surface layer, resulting in a decrease in the wear resistance, and the wear value reaches 256.8 mg / 1000r.

[0142] In summary, the product of the present application has excellent wear resistance and high long-span bending strength, and is suitable for outdoor weather-resistant, wear-resistant, and long-span polyvinyl chloride composites.

[0143] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit the present application. Although the present application is described in detail with reference to the above embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the above embodiments can be modified, or some or all of the technical features can be replaced equivalently without departing from the spirit and essence of the present application defined in the claims of the present application.

Claims

1. A bending-resistant polyvinyl chloride foamed co-extruded composite material, characterized in that, The composite material comprises a co-extrusion formed surface layer and core layer; the raw material mass ratio of the surface layer to the core layer is 0.5-0.8:10; the core layer further comprises a reinforcing layer formed by a continuous glass fiber mesh; The raw material for preparing the surface layer comprises the following components in parts by weight: ASA resin 70-80 parts, chlorinated polyether 20-30 parts, ASA color master batch 0.3-0.8 parts; The raw material for preparing the core layer comprises the following components in parts by weight: polyvinyl chloride resin 65-80 parts, modified calcium carbonate 20-25 parts, heat stabilizer 3-5 parts, lubricant 0.4-0.6 parts, coupling agent 0.8-1.0 parts, foaming agent 0.7-1.1 parts, modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin 10-13 parts, carboxyl polyester resin 3-4 parts, PVC color master batch 0.1-0.3 parts; The glass fiber mesh is a glass fiber mesh treated by a methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive; The modified calcium carbonate is a calcium carbonate modified by a methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive; The modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin is prepared by the following method: (1) 37% formaldehyde aqueous solution, methanol are added into a reaction kettle, stirring is started and the system is uniformly stirred, then 10-15% sodium hydroxide aqueous solution is used to adjust the pH value of the system to 8.0-9.0, then melamine and 1,3-bis(4'-aminophenoxy) benzene are added, and the temperature is raised to 65-70℃, and a polymerization reaction is carried out under insulation; the molar ratio of the raw materials is melamine: 1,3-bis(4'-aminophenoxy) benzene: formaldehyde: methanol = 1:0.3-0.4:7.5-8.8:2.5-3.0; (2) after the reaction system is free of insoluble substances and becomes homogeneous, the temperature is lowered to 40-50℃, concentrated sulfuric acid is added to adjust the pH value to 3.0-4.0, and the polymerization reaction is continued under insulation; (3) sampling detection is carried out, when the viscosity of the system is 120-140 mPa.s, 10-15% sodium hydroxide aqueous solution is added again to adjust the pH value in the system to 9.0-10.0, the temperature is raised and vacuum distillation is carried out, the vacuum degree is controlled at -0.096 to -0.098 Mpa, and the distillation temperature is 90-95℃; (4) the volatile content of the reactants in step (3) is detected by sampling, when the volatile content is 7-10%, the vacuum system is removed, and hexamethoxymethyl melamine powder is added, the mixture is uniformly stirred, the material is discharged, and is placed in a vacuum oven for drying treatment, the oven temperature is 85-90℃, the vacuum degree is -0.098 to -0.099 Mpa, when the volatile content is less than 2%, the material is taken out, is crushed to 60-80 mesh powder, and the modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin powder is obtained, wherein the molar amount of hexamethoxymethyl melamine is 0.1-0.12 times the molar amount of melamine.

2. The bending-resistant polyvinyl chloride foamed co-extruded composite material according to claim 1, characterized in that, The methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is prepared by the following method: (1) 37% formaldehyde solution, methanol are added into a reaction kettle, stirring is started and the system is uniformly stirred, then 10-15% sodium hydroxide solution is used to adjust the pH value of the system to 8.0-9.0, then melamine and 1,3-bis(4'-aminophenoxy) benzene are added, and the temperature is raised to 65-70°C for polymerization reaction; wherein the molar ratio of raw materials is melamine: 1,3-bis(4'-aminophenoxy) benzene: formaldehyde: methanol = 1:0.3-0.4:7.5-8.8:2.5-3.0; (2) After the reaction system becomes homogeneous without insoluble matter, the temperature is lowered to 40-50°C, concentrated sulfuric acid is added to adjust the pH value to 3.0-4.0, and the polymerization reaction is continued; (3) Sampling detection is performed, when the viscosity of the system is 120-140 mPa.s, 10-15% sodium hydroxide solution is added again to adjust the pH value in the system to 9.0-10.0, the temperature is raised and vacuum distillation is carried out, the vacuum degree is controlled at -0.096 to -0.098 MPa, and the distillation temperature is 90-95°C; (4) Sampling detection is performed on the volatile content of the reactants in step (3), when the volatile content is 30-35%, the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is obtained.

3. The bending-resistant polyvinyl chloride foamed co-extruded composite material according to claim 1, characterized in that, The heat stabilizer is a complex of calcium stearate and zinc stearate, and the mass ratio of the two is 2:1-1.3; The lubricant is stearic acid or hexadecanoic acid; The coupling agent is silane coupling agent JH-M902 or silane coupling agent KH-540; The foaming agent is azodicarbonamide.

4. The bend-resistant, polyvinyl chloride, foamed, co-extruded composite material of claim 1, wherein, The acid value of the carboxyl polyester resin is 25-29 mgKOH / g.

5. A process for the production of the flexurally resistant polyvinyl chloride foamed co-extruded composite material according to any one of claims 1 to 4, characterized in that, The following steps are included: (1) The formula amount of ASA resin, chlorinated polyether, ASA color master batch is fully mixed and uniformly mixed at room temperature, then melt extrusion granulation is carried out through a double screw extruder to obtain a surface layer granular material for standby; (2) The formula amount of polyvinyl chloride resin, methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive modified calcium carbonate, heat stabilizer, lubricant, coupling agent, modified melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin, carboxyl polyester resin, foaming agent, PVC color master batch are first fully mixed and uniformly mixed at room temperature, then they are crushed to a particle size of 70-100 mesh through a high-speed crusher to prepare a core layer premix for standby; (3) According to the mass ratio, the surface layer granular material and the core layer premix are taken, the core layer premix and the surface layer granular material are respectively melted through different double screw extruders, and then are respectively introduced into the core layer cavity and the surface layer cavity of the co-extrusion die, wherein the glass fiber mesh cloth treated by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is fixedly placed at the middle 1 / 2 of the core layer cavity, the core layer melt fills the core layer cavity and is fully combined with the glass fiber mesh cloth, the foaming and the surface layer co-extrusion molding are completed, and then the cooling molding, the surface layer surface embossing treatment and the fixed length cutting are carried out, so that the bending-resistant polyvinyl chloride foaming co-extrusion composite material is obtained.

6. The production method according to claim 5, wherein The preparation method of the calcium carbonate modified by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive comprises the following steps: The water-diluted methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive is sprayed on the surface of the calcium carbonate by using an automatic sprayer, the mass ratio of the adhesive to the calcium carbonate is 3-5:100, the calcium carbonate is continuously stirred to make the spraying uniform, after the spraying is completed, the calcium carbonate is fully mixed in a mixing machine for 10-15 min, and then is subjected to vacuum drying treatment, so that the modified calcium carbonate with a volatile content of less than 1% is obtained.

7. The preparation method according to claim 5, characterized in that The preparation method of the glass fiber mesh cloth treated by the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive comprises the following steps: The glass fiber mesh cloth is soaked in the methoxylated melamine-1,3-bis(4'-aminophenoxy) benzaldehyde resin adhesive for 20-30 s, is vertically hung to dry at room temperature until no liquid drops are dropped, is hung in an oven or a drying room for pre-curing treatment by using hot air, the temperature of the oven or the drying room is 80-85℃, and the time is 10-15 min, and then the glass fiber mesh cloth is cooled to room temperature.

8. The preparation method according to claim 5, characterized in that In step (1), the barrel temperature of the double screw extruder is 240-250℃, and the screw rotation speed is 150-200 rpm.

9. The preparation method according to claim 5, characterized in that In step (3), the barrel temperature of the core layer extrusion molding is 200-205℃, and the screw rotation speed is 10-20 rpm. The barrel temperature of the surface layer extrusion molding is 220-230℃, and the screw rotation speed is 10-20 rpm.

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