Method of production of the plates from compound materials

FIELD: construction materials production.

SUBSTANCE: invention relates to the production of the construction materials from waists of the wood processing industry; the method comprises filler fractionating and filler processing by the water solution of copolymer vinylcyclohexene with maleic anhydride followed by drying, adjustment of the modified wooden particles with polyethylene by means of mixing and heating followed by rolling on the laboratory rollers with the roller diameter of 180 mm and gapping between them of 1 mm, pressing of the received mass in the press-mould of the hydraulic pressing unit with the mark of origin ПГ-60 at the temperature of 180-210°C and pressure of MPa; the wood-polymer composites (WPC) is induced as an ingredient increasing the mechanical and physical characteristics of the compound and resistibility to UV irradiation, and thereafter the secondary polyethyleneterephthalate in the following proportions (%, mass): secondary polyethylen: 20.0-50.0; secondary polyethyleneterephthalate: 35.0-20.0; wooden particles: 37.5-22.5; CVMA: 2.5-7.5.

EFFECT: implementation of this method allows to increase physical, mechanical and ecological characteristics of the WPC plates.

2 tbl, 1 dwg

 

The invention relates to the production of building materials and can be used in the woodworking, furniture and construction industries.

A known method of manufacturing Spending on the basis of modified latex composition of urea-formaldehyde resins, including the processing of the composite particles of the binder followed by hot pressing (Iossifov and other Properties of chipboard on the basis of modified latex composition of urea-formaldehyde resins. The highest isotech. Institute, Sofia, IX Symposium, 9, 1989, str-189).

The disadvantages of this method are the use of styrene-butadiene latexes, not containing carboxyl groups, thickening additives in the form of a latex with a high content of methacrylic groups, and the absence of active filler capable of effectively adsorb residual formaldehyde. Emissions from ready-made plates of this compounds with carcinogenic and mutagenic properties complicates the use of plates in construction and virtually eliminates their use in the furniture industry.

There is a method of manufacturing a composite material (SLM, Ennevelin, Mphenylene / Wood-polymer composition on the basis of secondary materials industry // Izvestiya vuzov. Chemistry and the chemical is Skye technology. - 2001. - T. - V.2. - P.142-145), which includes several stages: fractionation of filler, processing the analyzed fraction with a solution of a synthetic rubber ethylene-propylene thermoplastic (Sept) nerase, followed by drying, a combination of modified wood particles with polyethylene by pre-mixing and heating with subsequent rolling on a laboratory roll mill with a roll diameter 180 mm and the gap between them is 1 mm, the pressing of the mass in the mold of a hydraulic press brand PG-60 at a temperature of 130-140°C and a pressure of 5 MPa, drevesnoplitnye composite WPC contains these components in the following ratio, wt.%:

secondary polyethylene59,0-70,5
wood particles27-38
SKEPT2,5-3,0

As wood waste used sawdust produced in large quantities in timber production from sliding table saw machine, saw devices, etc. secondary plastic raw materials in accordance with THE 63-476-32-90 Raw material polymer secondary raw" was a disused film and film products.

The disadvantages of this method are the relatively low strength and water resistance of the plates, as well as technological and environmental negative effects associated with certain requirements on the composition of the starting components of the composite binder.

Closest to the technical nature of the method of manufacturing a composite material (U.S. Pat. 2356728 Russian Federation, IPC B27N 3/00 08L 97/02, the Method of fabrication of a composite material / Ocelli S., Semenova L.K.; Appl. 21.02.2007; publ. 27.05.2009, bull. No. 15), which includes fractionation of filler, processing of filler with an aqueous solution of a copolymer vinylcyclohexane with maleic anhydride RAS, followed by drying, a combination of modified wood particles with a thermoplastic binder in the form of recycled polyethylene by pre-mixing and heating with subsequent rolling on a laboratory roll mill with a roll diameter 180 mm and the gap between them is 1 mm, the pressing of the mass in the mold of a hydraulic press brand PG-60 at a temperature of 130-140°C and a pressure of 5 MPa, in the following ratio, wt.%:

secondary polyethylene59,0-70,5
wood particles27-38/td>
RAS2,5-3,0

The disadvantages of this method of producing slabs of composite material are relatively low physical and mechanical properties of plates and low resistance to UV irradiation, which reduces the period of operation under atmospheric conditions and significantly reduces the scope.

Object of the invention is the improvement of physico-mechanical properties of plates and their resistance to UV-irradiation on the basis of a complex thermoplastic binder formed by replacing part of the recycled polyethylene secondary terephthalate.

To solve this problem in a known method of manufacturing WPC, including fractionation of filler, processing of filler SVM solution, followed by drying, a combination of modified wood particles with polyethylene by pre-mixing and heating with subsequent rolling on a laboratory roll mill with a roll diameter 180 mm and the gap between them is 1 mm, the pressing of the mass in the mold of a hydraulic press brand PG-60 at a temperature of 180-210°C. and a pressure of 5 MPa, the KDP is introduced as a thermoplastic binder that improves the physico-mechanical properties and resistance to UV-irradiation in the form of recycled polyethylene terephthalate (PET) the place part of recycled poly (ethylene terephthalate in the following ratio, wt.%:

secondary polyethylene20,0-50,0
secondary terephthalate35,0-20,0
wood particles37,5-22,5
RAS2,5-7,5

The positive effect of the proposed technical solutions, namely improving the strength and stability of the finished plates to UV irradiation is achieved by the introduction of the duodenum instead of recycled polyethylene secondary terephthalate. The latter allows to raise efficiency of use of recycled poly (ethylene terephthalate in the form of all kinds of packaging, including numerous bottles of Pat, who invaded the territory of Russia and, until recently, did not find its qualified use.

The resulting effect of the proposed use of the binder composition can be explained as follows.

The chemical nature of polyethylene terephthalate unlike chain polyethylene has a heterochain character, which has a higher physico-mechanical, elastic properties, resistance to aggressive environments, including harsh UV is Lucania, which is present in the spectrum of sunlight.

This invention will serve as an additional incentive for qualified use of secondary raw materials and improve the efficiency of existing enterprises.

The method according to the prior art (example 1 in table 1).

Manufacture of pressed plates made of composite material consisted of several stages: fractionation of filler, processing the analyzed fraction with a solution of a substance that improves the compatibility of the hydrophilic filler with a hydrophobic polyethylene, a combination of modified wood particles with polyethylene by pre-mixing and heating with subsequent rolling on a laboratory roll mill with a roll diameter 180 mm and the gap between them is 1 mm, the pressing of the mass in the mold of a hydraulic press brand PG-60 at a temperature of 130-140°C., a pressure of 5 MPa and time compression to 0.63-0.81 mm/min

Make a single layer plate thickness of 12 mm After pressing each plate is cooled in an upright position without blowing at room temperature. Test plates held not earlier than 5 days after production.

The proposed method (examples 2-6 of table 1) is as follows.

Manufacture of pressed plates made of composite material consisted of several stages: fractionation Napo the preserver, processing the analyzed fraction with a solution of a substance that improves the compatibility of the hydrophilic filler with a hydrophobic polyethylene, a combination of modified wood particles with polyethylene and polyethylene terephthalate by pre-mixing and heating with subsequent rolling on a laboratory roll mill with a roll diameter 180 mm and the gap between them is 1 mm, the pressing of the mass in the mold of a hydraulic press brand PG-60 at a temperature of 180-210°C., a pressure of 5 MPa and time compression of 0.42-0.58 mm/min After which the mold is cooled rapidly in water-salt solution with a temperature of -20÷-23°C for 2-3 minutes.

Make a single layer plate thickness of 12 mm Test plates held not earlier than 5 days after production.

In accordance with the present technology has received Board prototype (example 1) and the proposed method, by changing the composition of the material and technological conditions (examples 2-6 table 1).

td align="center"> 5
Table 1
ComponentsContent, wt.% for example
1 (prototype)2346
Secondary polyethylene65,0012,0025,0037,0050,0062,0
Wood particles30,0043,7537,5030,0022,5015,0
Secondary terephthalate-43,0035,0028,0020,0013,0
RAS5,001,252,505,007,5010,0

Plates with different composition composite material manufactured according to the above technologies were subjected to tests on the physico-mechanical properties and the content of free formaldehyde. The parameters of the tested slabs are shown in table 2.

Table 2
IndicatorsExamples
1 (prototype)23456
The tensile strength in bending, MPa15,3013,218,9022,519,514,2
The tensile strength in bending after 200 h of UV irradiation, MPa9,188,5812,2918,0to 12.287,40
The ultimate tensile stress parallel to the plate, MPa9,56of 7.9011.87 per13,712,648,10
Swelling in thickness, %0,650,750,490,320,58 0,81
30 days
Water absorption by weight, %1,231,621,110,931,051,17
30 days
Density, kg/m3820760805815815770
The content of free formaldehyde, mg/100 g sample2,482,830,510,210,472,49

As shown in table 2, data plate, obtained by the proposed method have higher strength properties and water resistance, significantly lower formaldehyde emission and significantly exceed the level of a prototype for resistance to UV radiation.

Despite the increase in the temperature of the pressing 140-160°C for prototype to 180-210°C by the proposed method significantly reduces the cycle pressing from 0.63-0.81 mm/is in to 0.42-0.58 mm/min When this pressing cycle ends with the sudden cooling of the molds in water-salt mixture with a temperature of -20÷-23°C for 2-3 min versus 1.5 to 2.0 hours of the prototype, where the gradual cooling of the press mass. Sharp cooling avoids crystallization of polyethylene terephthalate, to preserve the advantages of the amorphous state (transparent, elastic properties) and to significantly improve the performance of forging equipment.

Thus, it is possible to talk about a significant difference of the proposed method from the analogue and the resulting effect in the form of better products on the basis of waste polymer and plant materials.

A method of manufacturing particle boards from waste wood processing industry, including fractionation of filler, processing of the filler with a solution of a copolymer vinylcyclohexane with maleic anhydride (RAS) in nerase, followed by drying, a combination of modified wood particles with polyethylene by pre-mixing and heating with subsequent rolling on a laboratory roll mill with a roll diameter 180 mm and the gap between them is 1 mm, the pressing of the mass in the mold of a hydraulic press brand PG-60 at a temperature of 180-210°C. and a pressure of 5 MPa, the KDP enter as an ingredient that improves the physico-IU adicheskie performance and resistance to UV-irradiation, secondary terephthalate in the following ratio, wt.%:

secondary polyethylene20,0-50,0
secondary terephthalate35,0-20,0
wood particles37,5-22,5
RAS2,5-7,5



 

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Chipboard // 2355569

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EFFECT: enhanced physico-mechanical and ecological characteristics.

2 tbl

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1 dwg, 1 tbl

FIELD: manufacture of substantially flat articles, for instance particle boards and other articles of industrial wood residue or vegetable raw materials by hot pressing thereof.

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EFFECT: increased ecological safety and increased strength of the panels.

4 cl, 1 tbl, 1 ex

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EFFECT: facilitated procedure of production of composition.

1 tbl

FIELD: wood-working industry.

SUBSTANCE: fiber or chip is dried, then it is mixed with glue at a temperature of below 100C, and a plate is formed at a temperature above 140C, wood is decomposed into solid and liquid components that are used as the glue. The installation for manufacture of the plate has a drying device, device for application of glue onto the fiber or chip, device for compaction, transport facilities for transferring the fiber or chip from the drying device to the device for application of glue, mixer having means for cooling the body. The contents of glue in a plate obtained with the use of the installation makes up 45 to 55 kg per cubic meter of plate.

EFFECT: produced plate with a lower contents of glue as compared with plates produced by the known methods.

31 cl, 2 dwg

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EFFECT: improved strength and water tightness, and increased efficiency in utilization of various wastes.

2 tbl

FIELD: wood-working industry, and namely the method of manufacture of the structural unit, in particular, slab of wood fiber, wood chip and/or sawdust, and pressing of fiber, chip, and/or sawdust with applied glue for formation of the structural unit, in particular, slab.

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EFFECT: produced an ecologically pure method for manufacture of slabs and a device for its realization.

46 cl, 3 dwg

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