RU1822405C - Wood particle board molding compound - Google Patents

Abstract

SUMMARY OF THE INVENTION: the press composition contains (in wtD) a polyvinyl acetate emulsion (at a viscosity of 60-90 ° C according to R.Z-H), and the rest is wood particles. Single-layer plates are pressed at -180-200 ° C, 3 MPa, 1 min / mm plate thickness Sample characteristics: thicknesses, plates 10 mm, density 650 kg / m3, tensile strength, MPa, with a static bend of 18 - 20.5 , when stretched perpendicular to the layer 0.38-0.55, non-toxic, dynamic. Young's modulus, MPa 1150-2300. 2tab.

Description

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WITH

The invention relates to the woodworking industry, in particular, to the production of wood-based panels and can be used in the production of acoustic wood-based panels

A known wood board press composition comprising wood particles and a phenol-formaldehyde binder.

Also known is a wood board press composition comprising wood particles and a urea-formaldehyde binder.

A disadvantage of the known press compositions is the inability to use it to produce acoustic plates for housings of household electronic equipment due to their low sound and vibration absorption, and their high weight and mass.

A stranded invention is an increase in the acoustic properties of plates and a decrease in their density.

The technical solution presented in the invention has the following differences from the prototype.

As a binder, the press composition contains a polyvinyl acetate emulsion in the following ratio of components, wt.%:

Polyvinyl acetate

emulsions GOST 18992-80

Wood particles Else

The press composition is prepared as follows.

Example 10

For the composition, a GOST 18992-80 polyvinyl acetate emulsion with a viscosity of 60 NF sec in accordance with B3 in an amount of 15 m SD is taken and mixed with wood00

YU

 go

4 ABOUT

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particles (the rest) “Chips are taken mainly from aspen as wood particles, moisture content up to the width of the chip is about 1 mm, its length is about 10 mm, and its thickness is 0.2-0, A mm,

Next, they form a carpet and press single-layer plates with a flat metol

pressing at a temperature of 180-200

pressure 3 MPa, with a shutter speed of 1 min / mm plate thickness

Finished boards are subjected to physical and mechanical tests.

Examples of press compositions are presented in table. 1.

Physico-mechanical parameters of the gypsum boards are presented in table. 2 „

An analysis of the experimental results showed that, with a decrease in the content of polyvinyl acetate emulsion, it was on May 20. %, the required strength of the plates is not achieved, and with an increase in its content of more than 0 wt. $ did not reach

Polyvinyl acetate

emulsion, May .; 15 2P 30 L0 1 (5

(Wood particles Else Else Else Else Else Lethal

necessary vibration absorbing properties are also present.

The invention will make it possible to obtain a plate material with improved acoustic properties and reduced density, intended for use as a material for housings of household electronic equipment.

Claims (1)

The claims A press composition for wood boards, including wood chips and a synthetic binder, characterized in that, in order to increase the acoustic properties of the boards and reduce their density, it contains a polyvinyl acetate emulsion as a binder in the following ratio, wt. %: Poly vinil cetatite emulsion (50 & concentration) Log wood chips Lethal Table 1 table 2