CN104761820A

CN104761820A - Method for preparing polypropylene-based wood-plastic composite material by using rice husk powder

Info

Publication number: CN104761820A
Application number: CN201510199920.5A
Authority: CN
Inventors: 李欣; 凌敏; 李静静; 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 polypropylene-based wood-plastic composite material by using rice husk powder. The method comprises the following steps: screening the rice husk powder by a 40-mesh screen, performing alkalization treatment in a sodium hydroxide water solution, then washing with distilled water for 4-5 times, removing alkali and other impurities on the rice husk powder and finally performing drying treatment at 95 DEG C for 6h to prepare the rice husk powder for later use; weighing the raw materials according to the condition that the mass ratio of polypropylene to a dispersion and lubrication agent to a coupling agent to an antioxidant to rice husk powder is equal to (70-90):(4-10):(3-5):(0.2-0.6):(80-100); performing melting and plasticization on polypropylene by a plasticator at 175-185 DEG C, then sequentially adding the antioxidant, the rice husk powder, the dispersion and lubrication agent and the coupling agent, performing tight milling for 5-7 times, and then discharging sheets to prepare plasticized sheets; and putting the plasticized sheets on a flat plate vulcanizing machine for pressing to prepare the polypropylene-based wood-plastic composite material. The method disclosed by the invention is simple to operate and easy for realization large-scale popularization and application; and furthermore, by adding various processing additives, the compatibility between polypropylene matrix resin and wood dust is improved, and the processability and related mechanical property of the wood-plastic composite material are further improved.

Description

A kind of method utilizing powdered rice hulls to prepare polypropylene base 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 polypropylene base wood-plastic composite material.

Background technology

Containing wood powder and plastics in wood plastic composite, therefore matrix material has had the advantage of timber and plastics concurrently: 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.

Powdered rice hulls wide material sources, are a kind of energy-conserving and environment-protective biomass materials, can be used as the wood powder of wood plastic composite.From the angle of raw materials for production, wood plastic composite slows down and eliminates the public hazards pollution of plastic refuse, also eliminates rice husk waste material and piles up and burn the pollution brought to environment.

Along with the development of plastics industry, a large amount of waste or used plastics becomes rubbish, causes environmental pollution.In actual life, the large percentage that waste and old polypropylene occupies, and reclaim easily, price is lower.Therefore it becomes a kind of plastic raw materials of wood plastic composite.

Summary of the invention

The object of this invention is to provide a kind of method utilizing powdered rice hulls to prepare polypropylene base 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, polypropylene: dispersed lubricant: coupling agent: oxidation inhibitor: powdered rice hulls=70 for subsequent use ~ 90:4 ~ 10:3 ~ 5:0.2 ~ 0.6:80 ~ 100 that step (1) is obtained.

(3) the polypropylene fusion plastification on the plastics processing mill of 175 ~ 185 DEG C step (2) taken, then oxidation inhibitor, powdered rice hulls, dispersed lubricant and coupling agent that step (2) takes is added successively, slice after thin-pass 5 ~ 7 times, obtained plasticized sheet material.

(4) vulcanizing press is heated, the temperature arranging top plate is 175 ~ 185 DEG C, the temperature of lower bolster is 175 ~ 185 DEG C, treat that temperature rises to the temperature of setting, constant temperature 10 minutes, to be then placed on vulcanizing press preheating 4 minutes, pressurization 9 ~ 11Mpa mold pressing 4 minutes by plasticized sheet material obtained for step (3), be placed in pressurization 9 ~ 11Mpa on normal temperature vulcanizing press again to cold pressing 5 minutes, i.e. obtained polypropylene base wood-plastic composite material.

Described dispersed lubricant is containing the mixture of aromatic hydrocarbons, modified alkyl resol and fatty alcohol and fatty acid ester.

Described coupling agent is one or both in isocyanic ester and maleic anhydride.

Described oxidation inhibitor be three the last of the ten Heavenly stems ester.

The inventive method is simple to operate, is easy to large-scale promotion application, and adding by various processing aid, improve the consistency between polypropylene matrix resin and wood powder, thus improve the processing characteristics of wood plastic composite and relevant mechanical property.

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, polypropylene: dispersed lubricant: coupling agent: oxidation inhibitor: powdered rice hulls=80:9:4:0.4:90 for subsequent use that step (1) is obtained.

(3) the polypropylene fusion plastification on the plastics processing mill of 180 DEG C step (2) taken, then oxidation inhibitor, powdered rice hulls, dispersed lubricant and coupling agent that step (2) takes is added successively, slice after thin-pass 6 times, obtained plasticized sheet material.

(4) vulcanizing press is heated, the temperature arranging top plate is 180 DEG C, the temperature of lower bolster is 180 DEG C, treat that temperature rises to the temperature of setting, constant temperature 10 minutes, to be then placed on vulcanizing press preheating 4 minutes, pressurization 10Mpa mold pressing 4 minutes by plasticized sheet material obtained for step (3), be placed in 10Mpa that normal temperature vulcanizing press pressurizes again to cold pressing 5 minutes, i.e. obtained polypropylene base wood-plastic composite material.

Described dispersed lubricant contains the mixture D eoflow A of 3.5 mass parts aromatic hydrocarbons S-105,3.5 mass parts modified alkyl resol TKM-M80 and 2 mass parts fatty alcohol and fatty acid ester.

Described coupling agent is the mixture of 2 mass parts isocyanic ester and 2 mass parts maleic anhydrides.

The flexural strength of the polypropylene base wood-plastic composite material that the present embodiment obtains is 44.872MPa, and modulus in flexure is 4.117GPa, and shock strength is 19.032KJ/m ², tensile strength is 21.475 MPa, and torque capacity is 21.99Nm, and balancing moment is 4.51Nm, shows comparatively excellent mechanical property and processing characteristics.

Claims

1. utilize powdered rice hulls to prepare a method for polypropylene base 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, polypropylene: dispersed lubricant: coupling agent: oxidation inhibitor: powdered rice hulls=70 for subsequent use ~ 90:4 ~ 10:3 ~ 5:0.2 ~ 0.6:80 ~ 100 that step (1) is obtained;

(3) the polypropylene fusion plastification on the plastics processing mill of 175 ~ 185 DEG C step (2) taken, then oxidation inhibitor, powdered rice hulls, dispersed lubricant and coupling agent that step (2) takes is added successively, slice after thin-pass 5 ~ 7 times, obtained plasticized sheet material;

(4) vulcanizing press is heated, the temperature arranging top plate is 175 ~ 185 DEG C, the temperature of lower bolster is 175 ~ 185 DEG C, treat that temperature rises to the temperature of setting, constant temperature 10 minutes, to be then placed on vulcanizing press preheating 4 minutes, pressurization 9 ~ 11Mpa mold pressing 4 minutes by plasticized sheet material obtained for step (3), be placed in pressurization 9 ~ 11Mpa on normal temperature vulcanizing press again to cold pressing 5 minutes, i.e. obtained polypropylene base wood-plastic composite material;

Described dispersed lubricant is containing the mixture of aromatic hydrocarbons, modified alkyl resol and fatty alcohol and fatty acid ester;

Described coupling agent is one or both in isocyanic ester and maleic anhydride;