CN104761808A

CN104761808A - Method for preparing polyethylene-based wood-plastic composite material from rice husk powder

Info

Publication number: CN104761808A
Application number: CN201510199912.0A
Authority: CN
Inventors: 李欣; 李静静; 凌敏; 黄超
Original assignee: Guilin University of Technology
Current assignee: Guilin University of Technology
Priority date: 2015-04-25
Filing date: 2015-04-25
Publication date: 2015-07-08

Abstract

The invention discloses a method for preparing a polyethylene-based wood-plastic composite material from rice husk powder. According to the invention, rice husk powder is screened with a 40-mesh sieve; the rice husk powder is subjected to an alkalization treatment in a sodium hydroxide water solution, and is washed with distilled water; the obtained material is subjected to a drying treatment for 6h under a temperature of 95 DEG C, such that a rice husk powder material is obtained; raw materials are weighed according to a mass ratio that rice husk powder material to linear low-density polyethylene to dicumyl peroxide to monobutyltin oxide to silicone to dibutyl phthalate to methyltin is (20-60):(30-70):(0.1-1.7):(0.1-1.5):(8-14):(1-19):(0.5-4.5); the raw materials are well mixed in a high-speed mixer, such that a mixed material is obtained; reactive extrusion is carried out in a parallel twin-screw extruder, such that an extruded material is obtained; and a mold with the extruded material is pressed on a plate vulcanizing machine, such that the polyethylene-based wood-plastic composite material is obtained. The method provided by the invention is simple to operate. With the method, waste can be utilized. The method is suitable for large-scale popularization. The prepared polyethylene-based wood-plastic composite material is nontoxic and environmentally friendly. The material has excellent comprehensive performance, and is easy to process. The material can be used for replacing traditional wood, and has a good application prospect.

Description

A kind of method utilizing powdered rice hulls to prepare polyethylene based wood-plastic composite material

Technical field

The invention belongs to wood plastic composite preparing technical field, particularly a kind of method utilizing powdered rice hulls to prepare polyethylene based wood-plastic composite material.

Background technology

Containing wood powder and thermoplastic cement raw material in wood plastic composite, thermoplastic cement raw material wherein can adopt the dead meal of industry or life, powdered rice hulls wide material sources, is a kind of energy-conserving and environment-protective biomass material.Can be used as the wood powder of wood plastic composite.From the angle of raw materials for production, lignin plastics goods slow down and eliminate the public hazards pollution of plastic refuse, also eliminate rice husk waste material and pile up and burn the pollution brought to environment.Matrix material has had the advantage of timber and plastics concurrently simultaneously: 1. good processing characteristics.Wood plastic composite includes plastics and fiber, therefore, has the processing characteristics that same timber is similar, can saw, can follow closely, can dig, and use carpenter's utensil to complete, and nail-holding ability is obviously better than other synthetic materialss.Mechanical property is better than wood materials.Nail-holding ability is generally 3 times of timber, is 5 times of shaving board.2. good strength property.Wood plastic composite includes plastics, thus has good Young's modulus.In addition, due to including fiber and through fully mixing with plastics, thus there is the resistance to compression suitable with hardwood, the physical and mechanical properties such as counter-bending, and its wearing quality is obviously better than normal wood material.Surface hardness is high, is generally 2 ~ 5 times of timber.3. there is water-fast, corrosion resistant performance, long service life.Wood-plastic material and products thereof, can anti-strong acid-base, water-fast, corrosion-resistant compared with timber, and not bacterial growth, is not easily damaged by worms, not long fungi.Long service life, can reach more than 50 years.4. excellent adjustable performance.By auxiliary agent, the changes such as plastics can be polymerized, foam, solidify, modification, thus the characteristic such as density, intensity changing Wood-plastic material, can also reach anti-aging, anti-electrostatic, the particular requirement such as fire-retardant.

Because wood plastic composite has so many performance, just decide it will be widely used.1. construction industry.The floor of making by Wood Fiber Composites than superior many in low wood fibre board performance at present, not breathing, waterproof, surface aesthetic.If meet material for multilayer coextrusion section bar, internal layer adopts reclaimed materials, and outer employing virgin material, the every mechanical property of the goods made can compare favourably with hardwood products.2. the application of automobile industry.In recent years, Wood plastic boards, with its rational price, superior performance, is applied and is increased in automobile decoration material, as automobile door-plate, after put thing case, luggage case sidewall, seat plate etc.3. other industry.Except traditional industry, the Application Areas of matrix material constantly expands, started at present apply as pallet, flowerpot, handle for tool, office appliance, attack the engine components such as fast highway route marker, acoustic board and audio amplifier.

As everyone knows, polyethylene is one of four large general-purpose plastics in macromolecular material, and its consumption accounts for 60%.Along with the continuous expansion of polyethylene consumption market, the continuous variation of consumption kind, its poly waste amount is also in continuous increase.At present, the waste of the upper recoverable of annual society of China about has 1Mt, and what reality utilized about has 0.2Mt, 0.8Mt is also had to fail to be recycled, major part waste is disposed with land-fill method, so not only causes secondary pollution, also result in the profligacy of material.Along with science and technology, constantly progress and demand for energy constantly increase, how sooner, the recycling work relationship of carrying out waste better the rich and powerful of country and progress, and one of the recycling solving polyethylene waste important content during to be all waste thing recycle.

Summary of the invention

The object of this invention is to provide a kind of method utilizing powdered rice hulls to prepare polyethylene based wood-plastic composite material.

Concrete steps are:

(1) powdered rice hulls is crossed 40 mesh sieves, then be alkalinisation treatment 4 ~ 6 hours in the aqueous sodium hydroxide solution of 15 ~ 25% at mass percent concentration, alkalization temperature is 40 ~ 50 DEG C, and then with distilled water wash 4 ~ 5 times, alkali on removing powdered rice hulls and other impurity, last at 95 DEG C drying treatment 6 hours, obtained powdered rice hulls for subsequent use.

(2) raw material is taken according to following mass ratio, the powdered rice hulls for subsequent use that step (1) is obtained: linear low density polyethylene: dicumyl peroxide: Mono-n-butyltin: silicone: dibutyl phthalate: methyl tin=20 ~ 60:30 ~ 70:0.1 ~ 1.7:0.1 ~ 1.5:8 ~ 14:1 ~ 19:0.5 ~ 4.5, raw material is mixed on homogenizer, the rotating speed of homogenizer is 5000 ~ 9000 revs/min, obtained mixture.

(3) by mixture reactive extrursion in parallel double-screw extruder obtained for step (2), extruder temperature is set to 150 ~ 170 DEG C, rotating speed is 400 ~ 600 revs/min, and the residence time of material in screw rod is 4 ~ 6 minutes, obtained extruded material.

(4) vulcanizing press is heated, the temperature arranging top plate is 175 DEG C, the temperature of lower bolster is 175 DEG C, treat that temperature rises to the temperature of setting, constant temperature 30 minutes, mould to be placed between two templates preheating 30 minutes, then mould is opened, the extruded material that step (3) is obtained is put into the die cavity of mould, to cover in template that mould puts it to vulcanizing press preheating again 10 minutes, carry out first time exhaust, mold pressing 5 minutes under 8 ~ 10Mpa after exhaust, carry out second time exhaust again, then mold pressing 5 minutes under 8 ~ 10Mpa, cool, treat that temperature drops to 50 DEG C, pressure release, take out mould, and open, the plate be pressed into is taken out, naturally cooling under room temperature, i.e. obtained polyethylene based wood-plastic composite material.

The inventive method is simple to operate, utilization of waste material, is easy to large-scale promotion, and obtained polyethylene based wood-plastic composite material asepsis environment-protecting, high comprehensive performance, easily processes, and can substitute traditional timber, have a extensive future.

Embodiment

embodiment:

(1) powdered rice hulls is crossed 40 mesh sieves, then be alkalinisation treatment 5 hours in the aqueous sodium hydroxide solution of 20% at mass percent concentration, alkalization temperature is 45 DEG C, and then with distilled water wash 5 times, alkali on removing powdered rice hulls and other impurity, last at 95 DEG C drying treatment 6 hours, obtained powdered rice hulls for subsequent use.

(2) raw material is taken according to following mass ratio, the powdered rice hulls for subsequent use that step (1) is obtained: linear low density polyethylene: dicumyl peroxide: Mono-n-butyltin: silicone: dibutyl phthalate: methyl tin=40:50:0.9:0.8:11:10:2.5, raw material is mixed on homogenizer, the rotating speed of homogenizer is 7000 revs/min, obtained mixture.

(3) by mixture reactive extrursion in parallel double-screw extruder that step (2) is obtained, extruder temperature is set to 160 DEG C, and rotating speed is 500 revs/min, and the residence time of material in screw rod is 5 minutes, obtained extruded material.

(4) vulcanizing press is heated, the temperature arranging top plate is 175 DEG C, the temperature of lower bolster is 175 DEG C, treat that temperature rises to the temperature of setting, constant temperature 30 minutes, mould to be placed between two templates preheating 30 minutes, then mould is opened, the extruded material that step (3) is obtained is put into the die cavity of mould, to cover in template that mould puts it to vulcanizing press preheating again 10 minutes, carry out first time exhaust, mold pressing 5 minutes under 9Mpa after exhaust, carry out second time exhaust again, then mold pressing 5 minutes under 9Mpa, cool, treat that temperature drops to 50 DEG C, pressure release, take out mould, and open, the plate be pressed into is taken out, naturally cooling under room temperature, i.e. obtained polyethylene based wood-plastic composite material.

The shock strength of the polyethylene based wood-plastic composite material that the present embodiment obtains is 5.264 KJ/m ², tensile strength is 50.886 MPa, flexural strength 42.375 KJ/m ², water-intake rate is 2.998 %, all comparatively excellent.

Claims

1. utilize powdered rice hulls to prepare a method for polyethylene based wood-plastic composite material, it is characterized in that concrete steps are:

(1) powdered rice hulls is crossed 40 mesh sieves, then be alkalinisation treatment 4 ~ 6 hours in the aqueous sodium hydroxide solution of 15 ~ 25% at mass percent concentration, alkalization temperature is 40 ~ 50 DEG C, and then with distilled water wash 4 ~ 5 times, alkali on removing powdered rice hulls and other impurity, last at 95 DEG C drying treatment 6 hours, obtained powdered rice hulls for subsequent use;

(2) raw material is taken according to following mass ratio, the powdered rice hulls for subsequent use that step (1) is obtained: linear low density polyethylene: dicumyl peroxide: Mono-n-butyltin: silicone: dibutyl phthalate: methyl tin=20 ~ 60:30 ~ 70:0.1 ~ 1.7:0.1 ~ 1.5:8 ~ 14:1 ~ 19:0.5 ~ 4.5, raw material is mixed on homogenizer, the rotating speed of homogenizer is 5000 ~ 9000 revs/min, obtained mixture;

(3) by mixture reactive extrursion in parallel double-screw extruder obtained for step (2), extruder temperature is set to 150 ~ 170 DEG C, rotating speed is 400 ~ 600 revs/min, and the residence time of material in screw rod is 4 ~ 6 minutes, obtained extruded material;