CN105086232B - PVC base and preparation method thereof and PVC composite boards - Google Patents

Abstract

The invention discloses a PVC base material and a preparation method thereof and a PVC composite plate, wherein the PVC base material comprises the following raw materials in parts by weight: 60-80 parts of PVC, heavy sodium carbonate, 3-10 parts of stabilizer, 0.5-2 parts of balance lubricant, 0.5-2 parts of blowing agent, 5-10 parts of foam regulator; Wherein, PVC comprises SG-5 type PVC and SG-8 type PVC, the weight part of PVC and heavy sodium carbonate The ratio is 1:1‑1.3. The PVC composite board includes a PVC substrate and a semi-rigid PVC layer on the surface of the substrate. The advantage is that the PVC base material of the present invention has good continuous extrusion production capacity in production, the properties of the obtained base material are continuous and stable, the tensile strength and impact strength of the base material are very good, and the dimensional shrinkage rate is small; the PVC composite material of the present invention Compared with existing products, the board has higher mechanical strength and longer service life.

Description

PVC base material and its preparation method and PVC composite board

technical field

The invention relates to a board and a preparation method thereof, in particular to a PVC base material, a preparation method thereof and a PVC composite board.

Background technique

Plates are widely used in household manufacturing, construction and processing industries due to their excellent characteristics such as wide sources, various types, and easy processing. According to the molding structure, the panels can be roughly divided into solid wood panels, plywood, wood-plastic panels, plywood and decorative panels.

However, there are many problems in the existing boards, such as wood-plastic board, which is a new type of composite material integrating the advantages of wood and plastics, wherein "wood" is selected from waste wood, wood powder, wood fiber, sawdust, etc. Or straw, etc., "plastic" can be polyethylene, polypropylene, polystyrene, polyvinyl chloride and other polymers, supplemented with several additives, and produced by modern technology. Nowadays, wood-plastic panels are widely concerned by domestic and foreign markets due to their long service life, strong plasticity, environmental protection and health, and the realization of resource recycling; among them, the European and American markets represented by the United States and Canada The demand continues to increase, and it is mainly used in docks, railways, building doors and windows, and indoor furniture; in Asia, especially in countries with more developed economies, such as Japan, wood-plastic composite panels are usually used in dock construction, floors, and indoor furniture. However, most of the existing wood-plastic panels contain wood powder, and wood powder has many hidden dangers in the process of transportation, storage and maintenance, such as relatively easy to be affected by moisture, fire, and even formaldehyde pollution; at the same time, materials containing wood powder are extruded When it is not stable enough, it is prone to the phenomenon of difficulty in blanking and mold paste. In addition, other boards also have problems such as poor performance and difficult processing.

Therefore, urgently need to solve above-mentioned technical problem.

Contents of the invention

Purpose of the invention: the first purpose of the present invention is to provide a PVC substrate with better mechanical properties and longer service life;

The second object of the present invention is to provide the preparation method of this PVC substrate;

The third object of the present invention is to provide a PVC composite board, which is prepared by using PVC base material.

Technical solution: The PVC substrate of the present invention comprises the following raw materials in parts by weight: 60-80 parts of PVC, heavy sodium carbonate, 3-10 parts of stabilizer, 0.5-2 parts of balancing lubricant, foaming agent 0.5-2 parts, 5-10 parts of foam regulator; among them, PVC includes SG-5 type PVC and SG-8 type PVC, and the weight ratio of PVC to heavy sodium carbonate is 1:1-1.3.

In the present invention, SG-5 type PVC and SG-8 type PVC are used in combination to improve the mechanical properties of the substrate; preferably, the amount of SG-5 type PVC is 25-50 parts, and the amount of SG-8 type PVC is 50-25 parts. At the same time, the PVC of the present invention is preferably 70-75 parts.

The heavy sodium carbonate particle size that the present invention adopts is 800-1250 mesh; Its weight part is preferably 80-100 parts.

The balancing lubricant includes an inner lubricant and an outer lubricant.

The present invention also includes impact modifiers.

The preparation method of the PVC base material of the present invention comprises the following steps: preparing raw materials according to the weight ratio, performing high-speed mixing, material cooling, aging treatment, extrusion, crust foaming, cooling and setting in sequence to obtain the PVC base material.

The PVC composite board of the present invention comprises the above-mentioned PVC substrate and a semi-rigid PVC layer on the surface of the substrate.

Beneficial effects: Compared with the prior art, the present invention has the remarkable advantages that: the PVC base material of the present invention has good continuous extrusion production capacity in production, the properties of the obtained base material are continuous and stable, and the tensile strength and impact of the base material are The strength is very good, and the size shrinkage rate is small; the PVC composite plate of the present invention has higher mechanical strength and longer service life than existing products.

detailed description

The technical solutions of the present invention will be further described below in conjunction with the examples.

The invention provides a PVC substrate, which comprises the following raw materials in parts by weight: 60-80 parts of PVC, heavy sodium carbonate, 3-10 parts of stabilizer, 0.5-2 parts of balancing lubricant, and 0.5-2 parts of foaming agent. 2 parts, 5-10 parts of foam regulator; among them, PVC includes SG-5 type PVC and SG-8 type PVC, and the weight ratio of PVC to heavy sodium carbonate is 1:1-1.3.

The PVC resin of the present invention includes SG-5 type and SG-8 type; Wherein, SG-5 has higher average degree of polymerization and viscosity compared with SG-8, and " higher average degree of polymerization " here means better However, with the increase of the degree of polymerization, the plasticization of the material will become difficult, and the degree of plasticization of the resin will decrease. The substrate foam board of the present invention needs the resin to wrap a certain amount of gas under the condition of melting, and a certain amount of gas is required. If all SG-5 resins are used, the plasticization of the resins will be difficult, resulting in a decrease in the physical properties of the substrate. Therefore, in order to ensure the normal plasticization of the materials, the present invention chooses to use SG-5 and SG-8 resins in combination. , and using SG-5 to replace part of SG-8 can improve the thermal dimensional stability of the base material, and has a lower heating shrinkage rate and heating warpage rate. The addition of SG-5 resin in the present invention can improve the falcon groove overlap of the floor Tensile strength increases the lifespan of the floor. Preferably, the SG-5 type PVC is 25-50 parts, and the SG-8 type PVC is 50-25 parts. When the content of SG-5 type is less than that of SG-8 type, the base material with relatively lower density can be obtained, and the toughness of the obtained base material is better, which is suitable for flooring products with a thickness of more than 10mm; when the content of SG-5 type is higher than For the SG-8 type, the rigidity of the obtained base material is better, which can further improve the lap joint tensile strength of the floor falcon groove, so it is more suitable for use in floor products with a thickness of less than 6mm.

In the prior art, when producing floor boards, especially wood-plastic base boards, light calcium carbonate is used as a filler to enhance the hardness of the boards. The root cause of defects such as frequent paste is that the diameter of the light calcium carbonate used in the extruder is small, and the particles are easy to attract each other to form aggregates. But in the past, the common heavy calcium carbonate was not suitable for extruder production because of its large diameter. In the present invention, 800-1250 mesh superfine heavy calcium carbonate is selected, which is processed through ultrafine grinding and airflow pulverization, which is lighter High-quality calcium carbonate has good mobility, and its processing fluidity is obviously better than that of light calcium carbonate. Heavy calcium carbonate mainly plays the role of reinforcement and filler in the formula, because its main form is inorganic rigid particles, which have less fluidity and deformation than PVC molecules, and fine-grained calcium carbonate molecules can be embedded in PVC molecular chains Further reduce the deformation of its chain segment and play the role of reinforcement. The above mechanism of action determines that with the increase of the content of heavy calcium carbonate, the performance of the substrate will first increase and then decrease. Preferably, the content of heavy calcium carbonate in the material is 80-100 parts, and through repeated tests, the content of heavy calcium carbonate in the present invention is preferably 85-95 parts.

The balanced lubricants of the present invention include internal lubricants and external lubricants. Among them, the internal lubricant is mainly used to adjust the fluidity of the material, which is beneficial to processing. It can be G60, 3316A, etc., and the effect is similar. The content in the material is 0.6-0.8 parts, and more preferably 0.7-0.75 parts. The external lubricant is mainly to facilitate the extrusion of materials and improve processing efficiency. It can be PE wax, also known as polyethylene wax, or 1801. The effect is similar. The two can be used alone, and the effect is similar when used alone or in combination. In the material The content is 0.2-0.5 parts, preferably 0.25-0.4 parts.

The stabilizer of the present invention is a heat stabilizer, which can prevent thermal degradation of PVC. For example, it can be a calcium-zinc composite stabilizer, the models of which are LY21, YQ102, CZ96, etc., with similar effects. The content of the stabilizer in the material is preferably 6-7 parts.

The foaming agent of the present invention is an AC foaming agent and/or baking soda, wherein the content of the AC foaming agent in the material is 0.3-0.5 parts, and the content of the baking soda in the material is 0.5-0.7 parts.

The foaming regulator of the present invention is used to regulate the foaming of the foaming agent, promotes PVC plasticization, improves the PVC melt temperature, and prevents bubbles from merging or breaking. The foaming regulator can be LP-90, LS530, K400, and the effect is the same. Only the amount of addition is different, preferably, the content of the foam regulator in the material is 6-7 parts.

The present invention also includes an impact modifier, which is mainly used to increase the toughness and hardness of the PVC substrate, such as ACR, also known as acrylate, and its content in the material is 4-6 parts.

The invention also provides a preparation method for the PVC base material, which comprises the following steps: preparing raw materials according to the weight ratio, performing high-speed mixing, cooling the material, aging treatment, extrusion, crust foaming, cooling and setting in sequence to obtain the PVC base material.

Specifically, it includes: (1) Mixing of production materials: put the raw materials into a high-speed mixer according to the formula requirements, and mix them for 10-15 minutes at a speed of 1000-1300rpm until the temperature of the materials reaches 100-110°C, and then the temperature of the materials is reduced by cooling the mixer. The temperature is lowered to 30-35°C, and after the cooling is completed, the material is packed into bags for aging treatment for 12-24 hours. (2) Sheet material preparation: add the matured production material into the extruder, for example, it can be a conical twin-screw extruder (the barrel and mold temperature are set at 150-170°C), and pass through the foaming and crusting machine and cooling The setting machine is cooled and shaped, and finally cut into boards, which are PVC substrates.

A semi-rigid PVC layer is arranged on the PVC base material of the present invention to obtain a PVC composite board.

The semi-rigid PVC layer of the present invention comprises: 100-150 parts of SG-5 type PVC, 350-450 parts of heavy calcium carbonate, 3-4 parts of calcium-zinc composite stabilizer and dioctyl terephthalate (DOTP) 30 parts -40 parts, all in percent by weight. Since the semi-hard layer is formed by calendering, the fineness of calcium carbonate is not highly required, so the "heavy calcium carbonate" particles in it are relatively coarse, and the particle size can be about 160 mesh.

The preparation method of the semi-rigid PVC layer of the present invention comprises: (1) production material mixing: at first heavy calcium carbonate, calcium-zinc composite stabilizer, PVC resin, DOTP are thrown into high-speed mixer all at once according to the amount required by the formula, When the hot mixing temperature reaches 85-100°C, discharge the materials to the cold mixer for mixing. In order to ensure the uniformity of the mixing, the cold mixing time is set at 15 minutes, and the materials are discharged into the storage tank after completion. (2) Internal mixing: After 6 minutes of internal mixing, the mixed materials can be pushed to the open mixer. (3) Milling: The temperature of the mill is set at 170-180°C, and there is no fixed requirement for the milling time, which is determined by the speed of the mill and the material demanded by the calender. (4) Calendering: The roller pitch of the four calendering rollers is set to 1-2mm, the temperature is 170°C, and the speed ratio between the rollers is adjusted based on 0.9-1.2, and the speed ratio has a great influence on the dimensional shrinkage of the PVC layer. , need to be strictly controlled. (5) Shape cutting: When the thickness of the film meets the requirements, it is drawn to the cooling roller for shaping, and then cut into the required size.

Embodiment 1: the preparation of PVC substrate

Raw materials: 25 parts of SG-5 type PVC, 50 parts of SG-8 type PVC, 90 parts of 1250 mesh heavy sodium carbonate, 5 parts of calcium zinc composite stabilizer (LY21), 0.75 parts of internal lubricant (G60), external lubricant (PE wax) 0.35 parts, AC foaming agent 0.45 parts, baking soda 0.6 parts, foam regulator (LP-90) 6 parts.

Among them, SG-5 type PVC was purchased from Anhui Zhongtai, SG-8 type PVC was purchased from Dezhou Shihua, heavy calcium carbonate was purchased from Jurong Xingchen Stone Powder, LY21 was purchased from Honeywell in the United States, and G60 was purchased from Kunshan Magison , PE wax was purchased from BASF, Germany, AC foaming agent was purchased from Kunshan Maijisen, baking soda was purchased from Kunshan Maijisen, and LP-90 was purchased from Shandong Ruifeng Polymer.

Preparation method: Put the raw materials into a high-speed mixer according to the above formula, mix at a speed of 1000rpm for 10 minutes until the temperature of the material reaches 100°C, then cool the mixer to reduce the temperature of the material to 30°C, and pack the material into bags for aging treatment for 12 hours after cooling . Put the cured production material into the conical twin-screw extruder (the temperature of the barrel and mold is set at 150°C), pass through the foaming and crusting machine and the cooling and setting machine to cool and shape, and finally cut into boards, which is the PVC base material .

Embodiment 2: the preparation of PVC substrate

Raw materials: 50 parts of SG-5 type PVC, 25 parts of SG-8 type PVC, 85 parts of 800 mesh heavy sodium carbonate, 3 parts of calcium zinc composite stabilizer (YQ102), 0.6 parts of internal lubricant (3316A), external lubricant (1801) 0.2 parts, AC blowing agent 0.5 parts, foam regulator (LS530) 7 parts.

Among them, YQ102 was purchased from Honeywell in the United States, 3316A was purchased from Honeywell in the United States, 1801 was purchased from Kunshan Maggison, and LS530 was purchased from Ruifeng Polymer.

Preparation method: Put the raw materials into a high-speed mixer according to the above formula, mix at a speed of 1300rpm for 15 minutes until the temperature of the material reaches 110°C, then cool the mixer to reduce the temperature of the material to 35°C, and pack the material into bags for aging treatment for 20 hours after cooling . Put the cured production material into the conical twin-screw extruder (the temperature of the barrel and mold is set to 170°C), pass through the foaming and crusting machine and the cooling and setting machine to cool and shape, and finally cut into boards, which is the PVC base material .

Embodiment 3: the preparation of PVC substrate

Raw materials: 35 parts of SG-5 type PVC, 40 parts of SG-8 type PVC, 95 parts of 1000 mesh heavy sodium carbonate, 5 parts of calcium zinc composite stabilizer (CZ96), 0.8 parts of internal lubricant (G60), external lubricant (PE wax) 0.5 parts, AC foaming agent 0.3 parts, baking soda 0.5 parts, foam regulator (K400) 6 parts.

Among them, CZ96 was purchased from Honeywell in the United States, and K400 was purchased from Kunshan Maggison.

Preparation method: Put the raw materials into a high-speed mixer according to the above formula, mix at a speed of 1200rpm for 12 minutes until the temperature of the material reaches 105°C, then cool the mixer to reduce the temperature of the material to 32°C, and pack the material into bags for aging treatment for 24 hours after cooling . Put the cured production material into the conical twin-screw extruder (barrel and mold temperature set at 165°C), pass through the foaming and crusting machine and the cooling and setting machine to cool and shape, and finally cut into boards, which is the PVC base material .

Table 1 Performance comparison table of PVC substrates prepared in Examples 1-3

Example 4:

Raw materials: basically the same as in Example 1, the difference is: "25 parts of SG-5 type PVC, 50 parts of SG-8 type PVC" are replaced by "75 parts of SG-5 type PVC".

The preparation method is the same as in Example 1.

Example 5:

Raw materials: basically the same as in Example 1, the difference is: "25 parts of SG-5 type PVC, 50 parts of SG-8 type PVC" are replaced by "75 parts of SG-8 type PVC".

The preparation method is the same as in Example 1.

Embodiment 6:

Raw materials: basically the same as Example 1, the difference is: "1250 mesh heavy sodium carbonate" is replaced by "light sodium carbonate".

The preparation method is the same as in Example 1.

Table 2 Performance Comparison of PVC Substrates Prepared in Examples 4-6

Embodiment 7:

Raw materials: PVC includes SG-5 and SG-8, and the content of SG-5 in the material is less than that of SG-8 in the material; 90 parts of 1250 mesh heavy sodium carbonate, 5 parts of calcium-zinc composite stabilizer, internal lubrication 0.75 parts of agent (G60), 0.35 parts of external lubricant (PE wax), 0.45 parts of AC foaming agent, 0.6 parts of baking soda, and 6 parts of foam regulator (LP-90).

8 groups of parallel experiments were designed, and the total PVC content was 50, 55, 60, 70, 75, 80, 90 and 100 parts respectively.

The preparation method is the same as in Example 1.

Table 3 Performance comparison of substrates prepared with different contents of PVC resin as raw materials

Embodiment 8:

Raw materials: 25 parts of SG-5 type PVC, 50 parts of SG-8 type PVC, 90 parts of heavy sodium carbonate, 5 parts of calcium zinc composite stabilizer, 0.75 parts of internal lubricant (G60), 0.35 parts of external lubricant (PE wax) 0.45 parts of AC foaming agent, 0.6 parts of baking soda, 6 parts of foam regulator (LP-90).

Eight groups of parallel experiments were designed, and the particle sizes of heavy sodium carbonate were 600 mesh, 700 mesh, 800 mesh, 900 mesh, 1000 mesh, 1250 mesh, 1300 mesh, and 1400 mesh.

The preparation method is the same as in Example 1.

Table 4 Performance comparison of substrates prepared from heavy sodium carbonate with different particle sizes as raw materials

Embodiment 9:

Raw materials: 25 parts of SG-5 type PVC, 50 parts of SG-8 type PVC, 1250 mesh heavy sodium carbonate, 5 parts of calcium zinc composite stabilizer, 0.75 parts of internal lubricant (G60), 0.35 parts of external lubricant (PE wax) 0.45 parts of AC foaming agent, 0.6 parts of baking soda, 6 parts of foam regulator (LP-90).

Design 8 groups of parallel experiments, the contents of heavy sodium carbonate were 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, 100 parts and 110 parts respectively.

The preparation method is the same as in Example 1.

Table 5 Comparison of properties of substrates prepared with different contents of heavy sodium carbonate as raw materials

Embodiment 10: the preparation of semi-rigid PVC

Raw materials: 120 parts of SG-5 PVC, 400 parts of heavy calcium carbonate, 4 parts of calcium-zinc composite stabilizer and 35 parts of dioctyl terephthalate (DOTP), all in weight percent.

Preparation method: Put all the above materials into the high-speed mixer at one time, and when the hot mixing temperature reaches 90°C, discharge the materials into the cold mixer for mixing. In order to ensure the uniformity of the mixing, the cold mixing time is set to 15 minutes. Unload into hopper. Then start banburying, and after 6 minutes, the banburying good materials can be pushed to the open mixer. Then start the milling: the temperature of the mill is set at 175°C, and there is no fixed requirement for the milling time, which is determined by the speed of the mill and the production demand of the calender. Next, start calendering: the distance between the four calendering rollers is set to 2mm, the temperature is 170°C, and the speed ratio between the rollers is adjusted based on 1.0. The speed ratio has a great influence on the dimensional shrinkage of the PVC layer and needs to be strictly controlled. . Finally, shape cutting: when the thickness of the negative film meets the requirements, it is drawn to the cooling roller for shaping, and then cut to the required size.

Embodiment 11: Preparation of PVC composite board

Lay the semi-rigid PVC prepared in Example 10 on the surface of the base material prepared in Example 1. Specifically, after rolling glue on the surface of the base material, stick the semi-rigid PVC, keep the pressure at room temperature for 20 hours, and then go through cutting and locking. Buckle, get PVC composite board, and test its performance, the results are shown in Table 6.

Table 6 The performance test results of the PVC composite board prepared in Example 11

As can be seen from Table 6, the PVC composite sheet prepared in this example has good mechanical properties and good shrinkage properties: the lap joint of the falcon groove has high tensile strength, and the heat warpage and heat shrinkage rate are small. At the same time, the PVC composite board has moderate density, low residual sag and water absorption, excellent surface wear resistance and scratch resistance, and its comprehensive performance is superior to other similar products.

Claims (9)

1. A PVC substrate, characterized in that, comprises the following raw materials in parts by weight: 60-80 parts of PVC, heavy calcium carbonate, 3-10 parts of stabilizing agent, 0.5-2 part of balancing lubricant, 0.5 part of blowing agent - 2 parts, 5-10 parts of foam regulator; wherein, PVC includes SG-5 type PVC and SG-8 type PVC, and the weight-number ratio of PVC to heavy calcium carbonate is 1:1.13-1.27. 2. The PVC substrate according to claim 1, characterized in that: the SG-5 type PVC is 25-50 parts, and the SG-8 type PVC is 50-25 parts. 3. The PVC substrate according to claim 1, characterized in that: the PVC is 70-75 parts. 4. The PVC substrate according to claim 1, characterized in that: the particle diameter of the ground calcium carbonate is 800-1250 mesh. 5. The PVC substrate according to claim 1, characterized in that: the ground calcium carbonate is 80-100 parts. 6. The PVC base material according to claim 1, characterized in that: the balancing lubricant comprises an internal lubricant and an external lubricant. 7. The PVC substrate according to claim 1, further comprising an impact modifier. 8. according to the preparation method of the described PVC substrate of claim 1, it is characterized in that comprising the following steps: Raw materials are prepared according to the weight ratio, followed by high-speed mixing, material cooling, aging treatment, extrusion, crust foaming, cooling and shaping to obtain a PVC base material. 9. A PVC composite board, characterized in that it comprises a PVC base material and a semi-rigid PVC layer positioned on the surface of the base material; wherein the PVC base material is the PVC base material described in any one of claims 1-7 Or the PVC substrate prepared by the method described in claim 8.