CN105061851A - Long fiber reinforced polyolefin wood-plastic composite material and preparation method thereof - Google Patents

Abstract

The invention discloses a long-fiber reinforced polyolefin wood-plastic composite material and a preparation method thereof. The polyolefin wood-plastic composite material is composed of polyolefin resin, long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin ribbon material, compatibilizer, coupling agent, wood powder and inorganic filler, and is mixed by internal mixer Then enter the extruder to extrude pellets or products for extrusion molding or send them to the injection molding machine for injection molding. The addition of long-fiber reinforced polyolefin composite materials in the present invention can greatly improve the mechanical properties of wood-plastic composite materials such as strength, stiffness, toughness and hardness, thereby effectively improving the stiffness, toughness, surface hardness and grip of wood-plastic panels and profiled products. Nail force, etc.; the present invention can mix long fiber reinforced polyolefin composite material or its reclaimed material with wood powder, inorganic filler and other materials very uniformly through internal mixer; the wood-plastic material itself has been strengthened to make its performance better , a wider range of applications.

Description

A kind of long fiber reinforced polyolefin wood-plastic composite material and preparation method thereof

technical field

The invention belongs to the technical field of wood-plastic composite material and its preparation, in particular to a long-fiber reinforced polyolefin wood-plastic composite material and a preparation method thereof.

Background technique

Polyolefin wood-plastic composites usually refer to polyethylene, polypropylene or a blend of the two as the base material, adding wood powder, bamboo powder, rice husk powder and other biomass fillers, mineral fillers, lubricants and interface modification. Polyolefin-based wood-plastic composites composed of agents and the like. It is superior to PVC-based wood-plastic composite materials in terms of toughness, environmental protection and combustion emissions, and has been widely used in indoor and outdoor floors, wall panels, guardrails, fences, flower boxes, seats, etc.

The existing general wood-plastic composite materials have low mechanical properties such as strength, stiffness, toughness, and hardness, resulting in poor stiffness, toughness, surface hardness, and nail-holding force of wood-plastic panels and profiled products.

Patent CN104073012A discloses a basalt long fiber reinforced wood-plastic and its preparation method, including three steps of surface modified basalt long fiber, granulation and extrusion, and the surface-modified basalt long fiber is used to reinforce wood-plastic The material has good compatibility. Long basalt fibers are inserted into the openings of the third zone and the fourth zone respectively. When passing through the third zone, more fibers are cut into short and medium fibers of 3-10 mm. After passing through the fourth zone In the time zone, the shear force on the long fibers is small, and the fiber length is generally 10-20mm. In this way, 3-20mm of basalt fibers are distributed in the wood-plastic profile, and the weight of each component is reasonably selected. , the mechanical properties of the final product such as flexural strength, flexural modulus of elasticity, and impact strength have been significantly improved. The mixing element of the extruder in this method is mainly set in consideration of the continuous fiber yarn entering the extruder to keep a sufficient length. The mixing effect is limited, and it is difficult to mix the resin, wood powder, inorganic filler, and fiber evenly.

Patent CN104070663A discloses a process for continuous long-fiber reinforced wood-plastic products, which is characterized in that it includes the following steps: 1) subjecting long-fiber-reinforced PP sheets to surface flame treatment; 2) combining PVC wood-plastic particles with the processed The sheet can be co-extruded. Compared with the traditional preparation of wood-plastic products, the wood-plastic composite product prepared by the invention has excellent mechanical properties and stable dimensions during outdoor use under the premise of ensuring decorative effects. The product prepared by the method can be applied to the field of structural profiles, such as plank floors, fences, wooden houses, etc., thereby widening the use area of wood-plastic composite materials and having good social and economic benefits. However, this method only co-extrudes PVC wood-plastic particles and continuous fiber-reinforced PP sheets to form a composite board, and the wood-plastic material itself is not reinforced.

Contents of the invention

Aiming at the deficiencies of the prior art, the present invention provides a long-fiber reinforced polyolefin wood-plastic composite material and a preparation method thereof. The addition of long-fiber reinforced polyolefin composite materials can greatly improve the strength, stiffness, toughness and hardness of the wood-plastic composite material and other mechanical properties, thereby effectively improving the rigidity, toughness, surface hardness and nail-holding force of wood-plastic panels and profiled products; the present invention can combine long-fiber reinforced polyolefin composite materials or their recycled materials with wood flour, Inorganic fillers and other materials are mixed evenly; the wood-plastic material itself has been enhanced to make it perform better and have a wider range of applications.

To achieve the above object, the present invention is achieved through the following technical solutions:

A long-fiber reinforced polyolefin wood-plastic composite material, consisting of the following raw materials in mass percentage:

Polyolefin resin: 30-70%

Long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin tape material: 10-40%

Compatibilizer: 0~10%

Coupling agent: 0.1～1%

Wood flour: 10-30%

Inorganic filler: 0-20%.

The long-fiber-reinforced polyolefin granular material or the long-fiber-reinforced polyolefin ribbon material consists of the following raw materials in mass percentage:

Polyolefin resin: 40-70%

Fiber: 30-60%.

The long fiber reinforced polyolefin granular material or the long fiber reinforced polyolefin ribbon material is prepared by the following method: after the continuous fiber bundle is preheated and dispersed by the preheating roller, it passes through the molten polyolefin in the dipping die. After the olefin resin is impregnated, it is molded through a die to obtain continuous fiber reinforced polyolefin strips or tapes, which are cut into pellets or strips.

The polyolefin resin of the long-fiber-reinforced polyolefin granular material or the long-fiber-reinforced polyolefin ribbon material is polypropylene or polyethylene or recycled materials thereof, and the fiber is glass fiber, basalt fiber or carbon fiber.

The polyolefin resin is polypropylene or polyethylene or recycled materials thereof.

The compatibilizer is maleic anhydride grafted polyethylene or maleic anhydride grafted polypropylene; the coupling agent is a silane coupling agent or a titanate coupling agent; the inorganic filler is calcium carbonate or talcum powder .

A method for preparing the long-fiber reinforced polyolefin wood-plastic composite material, comprising the following steps:

1) drying the required wood powder and inorganic filler;

2) Mix the dried wood powder, inorganic filler and coupling agent evenly;

3) adding polyolefin resin, long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin ribbon material and compatibilizer to the internal mixer for mixing;

4) After the polyolefin resin, long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin strip material and compatibilizer are melted, the wood flour, inorganic filler and coupling agent described in step 2) are added to the banburying Mixing in the machine;

5) After the mixing is completed, unload the material, granulate, and send the pellets to the extruder for extrusion and pelletization or extrusion molding of the product or send it to the injection molding machine for injection molding.

The temperature of the internal mixer chamber is 150-230°C.

The temperature of the barrel of the extruder is 140-230°C.

The temperature of the barrel of the injection molding machine is 140-230°C.

The beneficial effects of the present invention are as follows:

Compared with the existing polyolefin wood-plastic composite material, the long-fiber reinforced polyolefin wood-plastic composite material of the present invention can greatly improve the strength, stiffness, toughness and Hardness and other mechanical properties, thereby effectively improving the stiffness, toughness, surface hardness and nail-holding force of wood-plastic boards and profiled products; the invention can uniformly mix long-fiber reinforced polyolefin composite materials or their recycled materials through internal mixers. It is evenly mixed with other materials such as wood flour and inorganic fillers; the wood-plastic material itself has also been enhanced to make it perform better and have a wider range of applications.

Detailed ways:

The present invention will be further described below in conjunction with embodiment, it is necessary to point out that this embodiment is only used to further illustrate the present invention, can not be interpreted as the restriction to protection scope of the present invention, those skilled in the art can according to above-mentioned present invention Make some non-essential improvements and adjustments to the content.

It is worth noting that the parts of materials used in the following examples and comparative examples are all mass fractions, the density of high-density polyethylene is 0.945g/cm ³ , the particle size of wood flour is 100 mesh, and the particle size of calcium carbonate to 10 microns.

Example 1

formula:

High-density polyethylene, 41.5%;

Long glass fiber reinforced polyethylene strip material (length 8mm, fiber content 50%, preparation method: after the continuous glass fiber bundle is preheated and dispersed by the preheating roller, after the molten polyethylene resin is impregnated through the dipping die , formed by a flat die to obtain a continuous fiber-reinforced polyethylene tape, then cut into a strip-shaped material with a length of 8 mm, the preheating temperature of the dispersing roller: 190 ° C, the temperature of the dipping die: 190 ° C), 20.0%;

Wood flour, 20%;

Calcium carbonate, 10%;

Titanate coupling agent, 0.5%;

Maleic anhydride grafted polyethylene, 8.0%.

Preparation:

1) Dry the required wood powder and calcium carbonate, and dry them in an oven at 80°C for 4 hours;

2) Add the dried wood flour, calcium carbonate and titanate coupling agent to a high-speed mixer (stirring speed: 500rpm) and mix evenly for 10 minutes;

3) Mix high-density polyethylene, long glass fiber reinforced polyethylene strip material and maleic anhydride grafted polyethylene evenly and then add them to the internal mixer for mixing. Set the temperature in the internal mixer chamber to 190°C, and mix time 3 minutes;

4) After the high-density polyethylene, long glass fiber reinforced polyethylene strip material and maleic anhydride grafted polyethylene are melted, the wood flour and titanate coupling agent described in step 2) are added to the internal mixer Mixing, mixing time 10 minutes;

5) After the mixing is completed, unload the material, granulate, and send the pellets to the injection molding machine for injection molding into mechanical performance splines. The set temperatures of the feeding section, plasticizing section, and anti-saliva section of the injection molding machine barrel are as follows: 150°C, 190°C, 190°C.

The long-fiber reinforced polyolefin wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 36.39MPa; bending strength: 58.66MPa; impact strength: 8.15kJ/m ² ; hardness (HD): 65.67.

Example 2

formula:

High-density polyethylene, 36.5%;

Long glass fiber reinforced polyethylene granular material (length 50mm, fiber content 50%, preparation method: after the continuous glass fiber bundle is preheated and dispersed by the preheating roller, after the molten polyethylene resin is impregnated through the dipping die, Formed by a cylindrical die to obtain continuous fiber reinforced polyethylene strips, and then cut into granular materials with a length of 50 mm, the preheating temperature of the dispersing roller: 210 ° C, the temperature of the dipping die: 210 ° C), 25.0%;

Wood flour, 30.0%;

Silane ester coupling agent, 0.5%;

Maleic anhydride grafted polyethylene, 8.0%.

Preparation method: The internal mixer chamber set temperature is 210°C, the set temperatures of the feeding section, plasticizing section, and anti-spill section of the injection molding machine barrel are as follows: 150°C, 210°C, and 210°C, and the rest are the same as in Example 1. same.

The long fiber reinforced polyolefin wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 44.79MPa; bending strength: 59.8MPa; impact strength: 8.32kJ/m ² ; hardness (HD): 70.

Example 3

formula:

High-density polyethylene, 59.5%;

Long glass fiber reinforced polyethylene strip material (length 5mm, fiber content 50%, preparation method: cutting length is 5mm, all the other are identical with embodiment 1), 10.0%;

Wood flour, 30.0%;

Silane coupling agent, 0.5%.

Preparation method: The internal mixer chamber set temperature is 170°C, the set temperatures of the feeding section, plasticizing section, and anti-spilling section of the injection molding machine barrel are: 140°C, 170°C, and 170°C, and the rest are the same as in Example 1. same.

The long-fiber reinforced polyolefin wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 31.27MPa; bending strength: 41.7MPa; impact strength: 5.4kJ/m ² ; hardness (HD): 64.33.

Example 4

formula:

Polypropylene, 30%;

Long glass fiber reinforced polypropylene strip (length 8mm, fiber content 50%, preparation method: same as Example 1), 40.0%;

Wood flour, 19.5%;

Silane coupling agent, 0.5%;

Maleic anhydride grafted polypropylene, 10.0%.

Preparation method: The internal mixer chamber set temperature is 230°C, the set temperatures of the feeding section, plasticizing section, and anti-spill section of the injection molding machine barrel are as follows: 160°C, 230°C, and 230°C, and the rest are the same as in Example 1. same.

The long-fiber reinforced polyolefin wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 47.01MPa; bending strength: 50.80MPa; impact strength: 8.80kJ/m ² ; hardness (HD): 75.41.

Example 5

formula:

Polypropylene, 50%;

Long glass fiber reinforced polypropylene granular material (length 50mm, fiber content 50%, preparation method: same as Example 2), 25.0%;

Wood flour, 16.0%;

Silane coupling agent, 1.0%;

Maleic anhydride grafted polypropylene, 8.0%.

Preparation method: The internal mixer chamber set temperature is 210°C, the set temperatures of the feeding section, plasticizing section, and anti-spill section of the injection molding machine barrel are as follows: 150°C, 210°C, and 210°C, and the rest are the same as in Example 1. same.

The long-fiber reinforced polyolefin wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 48.97MPa; bending strength: 55.23MPa; impact strength: 9.4kJ/m ² ; hardness (HD): 76.25.

Example 6

formula:

Polypropylene, 70%;

Long glass fiber reinforced polypropylene granular material (length 5mm, fiber content 50%, preparation method: cutting length 5mm, all the other are identical with embodiment 2), 10.0%;

Wood flour, 13.9%;

Titanate coupling agent, 0.1%;

Maleic anhydride grafted polypropylene, 6.0%.

Preparation method: set the temperature of the internal mixer chamber at 190°C, set the temperature of the feeding section, plasticizing section, and anti-spilling section of the injection molding machine barrel as follows: 140°C, 190°C, and 190°C, and the rest are the same as in Example 1. same.

The long-fiber reinforced polyolefin wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 41.36MPa; bending strength: 48.48MPa; impact strength: 8.30kJ/m ² ; hardness (HD): 68.46.

Example 7

formula:

Polypropylene, 40%;

Long glass fiber reinforced polypropylene granular material (length 8mm, fiber content 50%, preparation method: cutting length is 8mm, same as Example 2), 20.0%;

Wood flour, 20.0%;

Talc, 9%

Titanate coupling agent, 1.0%;

Maleic anhydride grafted polypropylene, 10.0%.

Preparation method: The internal mixer chamber set temperature is 230°C, the set temperatures of the feeding section, plasticizing section, and anti-spill section of the injection molding machine barrel are as follows: 160°C, 230°C, and 230°C, and the rest are the same as in Example 1. same.

The long fiber reinforced polyolefin wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 45.27MPa; bending strength: 52.39MPa; impact strength: 8.4kJ/m ² ; hardness (HD): 70.98.

Comparative example 1:

formula:

High-density polyethylene, 61.5%;

Wood flour, 30.0%;

Silane ester coupling agent, 0.5%;

Maleic anhydride grafted polyethylene, 8.0%.

Preparation:

1) Dry the required wood powder in an oven at 80°C for 4 hours;

2) Add the dried wood powder and silane coupling agent to a high-speed mixer (stirring speed: 500rpm) and mix evenly for 10 minutes;

3) Mix high-density polyethylene and maleic anhydride-grafted polyethylene evenly, then add them to the internal mixer for mixing, set the temperature in the internal mixer chamber to 190°C, and mix for 3 minutes;

4) After the high-density polyethylene and maleic anhydride grafted polyethylene are melted, add the wood powder and silane coupling agent described in step 2) into the internal mixer for mixing, and set the temperature of the internal mixer chamber at 190 ℃, mixing time 10 minutes;

5) After the mixing is completed, unload the material, granulate, and send the pellets to the injection molding machine for injection molding into mechanical performance splines. The set temperatures of the feeding section, plasticizing section, and anti-saliva section of the injection molding machine barrel are as follows: 150°C, 190°C, 190°C.

The wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 25.88MPa; bending strength: 32.84MPa; impact strength: 4.52kJ/m ² ; hardness (HD): 56.

Comparative example 2:

formula:

Polypropylene, 60%;

Wood flour, 20%;

Calcium carbonate, 9%;

Silane coupling agent, 1%;

Maleic anhydride grafted polypropylene, 10%.

Preparation method: same as Comparative Example 1.

The wood-plastic composite material prepared by the above method has the following mechanical properties: tensile strength: 26.00MPa; bending strength: 36.66MPa; impact strength: 4.72kJ/m ² ; hardness (HD): 50.

Comparing Examples 1-3 and Comparative Example 1, its polyolefin resins are all high-density polyethylenes. Among Examples 1-3, the mechanical properties of Example 3 are the smallest, but also larger than Comparative Example 1; the mechanical properties of Example 2 The performance is the best, and its tensile strength, bending strength, impact strength, and hardness are 1.73 times, 1.82 times, 1.84 times, and 1.30 times that of Comparative Example 1, respectively.

Comparing Examples 4-7 and Comparative Example 2, its polyolefin resins are all polypropylenes, and in Examples 4-7, the mechanical properties of Example 6 are the smallest, but also larger than Comparative Example 2; the mechanical properties of Example 5 are the most Well, its tensile strength, bending strength, impact strength, and hardness are 1.88 times, 1.51 times, 1.99 times, and 1.36 times that of Comparative Example 2, respectively.

Claims (10)

1. A long-fiber reinforced polyolefin wood-plastic composite material, characterized in that: it is made up of the following raw materials in mass percentage: Polyolefin resin: 30-70% Long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin tape material: 10-40% Compatibilizer: 0~10% Coupling agent: 0.1～1% Wood flour: 10-30% Inorganic filler: 0-20%. 2. A long-fiber-reinforced polyolefin wood-plastic composite material as claimed in claim 1, characterized in that: the long-fiber-reinforced polyolefin granular material or long-fiber-reinforced polyolefin ribbon material consists of the following raw materials in mass percentage : Polyolefin resin: 40-70% Fiber: 30-60%. 3. A long-fiber-reinforced polyolefin wood-plastic composite material as claimed in claim 2, characterized in that: the long-fiber-reinforced polyolefin granular material or long-fiber-reinforced polyolefin strip material is prepared by the following method : After the continuous fiber bundle is preheated and dispersed by the preheating roller, it is impregnated with the molten polyolefin resin in the impregnation die, and then shaped by the die to obtain continuous fiber reinforced polyolefin strips or tapes, which are cut into granular materials or Ribbon. 4. A long fiber reinforced polyolefin wood-plastic composite material as claimed in claim 2, characterized in that: the polyolefin resin of the long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin strip material is polypropylene Or polyethylene or its recycled materials, the fiber is glass fiber, basalt fiber or carbon fiber. 5. A long fiber reinforced polyolefin wood-plastic composite material as claimed in claim 1, characterized in that: said polyolefin resin is polypropylene or polyethylene or recycled materials thereof. 6. A long fiber reinforced polyolefin wood-plastic composite material as claimed in claim 1, characterized in that: the compatibilizer is maleic anhydride grafted polyethylene or maleic anhydride grafted polypropylene; The coupling agent is a silane coupling agent or a titanate coupling agent; the inorganic filler is calcium carbonate or talcum powder. 7. A method for preparing the long-fiber reinforced polyolefin wood-plastic composite material according to claim 1, characterized in that: comprising the following steps: 1) drying the required wood powder and inorganic filler; 2) Mix the dried wood powder, inorganic filler and coupling agent evenly; 3) adding polyolefin resin, long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin ribbon material and compatibilizer to the internal mixer for mixing; 4) After the polyolefin resin, long fiber reinforced polyolefin granular material or long fiber reinforced polyolefin strip material and compatibilizer are melted, the wood flour, inorganic filler and coupling agent described in step 2) are added to the banburying Mixing in the machine; 5) After the mixing is completed, unload the material, granulate, and send the pellets to the extruder for extrusion and pelletization or extrusion molding of the product or send it to the injection molding machine for injection molding. 8. The method for preparing long fiber reinforced polyolefin wood-plastic composite material according to claim 7, characterized in that: the temperature of the internal mixer chamber is 150-230°C. 9. The method for preparing long fiber reinforced polyolefin wood-plastic composite material according to claim 7, characterized in that: the temperature of the barrel of the extruder is 140-230°C. 10. The method for preparing long fiber reinforced polyolefin wood-plastic composite material according to claim 7, characterized in that: the temperature of the barrel of the injection molding machine is 140-230°C.