SU685678A1 - Polymeric press-composition - Google Patents

Description

The invention relates to the production of press articles based on phenolic resins subjected to high thermal loads.

A known press composition containing a phenolic binder, wood flour, hexamine, grease, lime polisher, dye and lithopone 1

Press products have good mechanical properties, but their thermal stability and heat resistance are small.

The purpose of the invention is the emergence of heat resistance and thermal stability of the composition.

This goal is achieved in that the composition as a phenolic binder contains a boron esterified etherified hexaphenol resin with a content of ester groups of 10-40% and additionally contains asbestos in the following ratio of components, wt.%:

Esterified

hexaphenol resin 32 -40

Wood flour 20 -23

Urotropin5 - 6

Lubricant1 5-2.5

Lime polishing 1 - 1.5 Dye 0.5-1

Lithopon4 - 6

Asbestos25-30.

The physicochemical indicators characterizing the properties of the esterified hexaphenol resin are given below.

Appearance

light yellow product

Viscosity of a 50% strength solution (in acetone), cp

15-40

Gel time (at 180 ° С with the addition of 10% hexamine), with

90-120

The content of free phenol,%

Not bo.pee 15

Shelf life, months

Not less than 9 Content of ortho-bonds,%

95-100 Content of ethereal groups%

10-40.

In the table below are examples of formulations of the proposed composition (1-3) and the composition of the known composition 1 of a press material of the brand Ж5-010-78 (4),

. T a b l and ri a

Component

Composition, wt.%

37

The proposed composition IXDTOBHT on conventional equipment in a known manner, i.e. mixing all the components, rolling the mixture, grinding.

To determine the physicomechanical and dielectric properties of the proposed composition, standard samples were prepared by the method of pressing and npf were used to test them according to GOST 5689-73. The results are shown below.

1.5-1.6

kg.cm

4.2-5.0

cm

Specific surface

- Not less electrical resistance, Ohm 5-10

Resistance to action

heat,%

4.0-5.0

but

Weight loss (at 300 ° C for 5 h),% 4.5-6.0.

Claims (1)

Invention Formula A polymer press composition containing a phenolic binder, ancient flour, urotropin, a lubricant, known as a polystyrene, a dye and lithopone, characterized in that, in order to increase the heat resistance and thermal stability, the content of ether groups 10-40% and additionally contains asbestos in the following ratio of components, wt.%: Esterified hexaphenol resin 32 -40 Wood flour 20 -23 Urotropin5 - 6 1.5-2.5 Grease 1.5 Lime polishing 0.51 6 Dye Lithopone Asbestos25-30 Information sources taken into account during the examination 1, Regulations of the Kemerovo Carbolit Plant No. P-143-74.