SU979403A1 - Composition for producing foamed plastic - Google Patents

Description

(54) COMPOSITION FOR OBTAINING FOAM PLASTIC FIELD OF THE INVENTION The invention relates to compositions for the preparation of foam based on resole-type phenol-formaldehyde resins used in pumping heat-insulating materials in construction and other areas of the national economy. A known composition for the preparation of a foam, containing a phenol-formaldehyde, a resole-type hydrating resin, a surfactant, aluminum powder and a foaming-curing agent. On the basis of this composition, commercially available foam is produced on the basis of a phenol-formaldehyde resin brand FRP-1. The disadvantage of the known foam is its low strength properties. In addition, the specified composition does not provide low density foam and, therefore, the required operational strength. If the weight decreases, the strength properties deteriorate, the foam is destroyed immediately after its manufacture. A known foam composition containing phenolic resole phenol form, resin modified with) methyl cellulose, aluminum powder, foam-curing agent 2. On the basis of the known composition, it is possible to obtain a foam with a rather low bulk density, however, due to the low content of the mainstream (dry residue 45%), its strength is low. 11 most closely related to the present invention is a composition comprising a resol phenol-formaldehyde resin, modified by the residual phenol production by the cumene method, a surfactant, aluminum powder and a foaming-hardening agent. The known composition provides a foam with improved strength properties with a bulk density of 80 above the SPZ. However, polystyrene foam with a suitable density of operation, on the basis of this composition could not be obtained. Low density is a valuable technical feature that provides lightweight construction, thermal insulation products with low thermal conductivity. In addition, the use of such a foam reduces the consumption of raw materials, the cost of foam.

The purpose of the invention is to obtain a high-strength foam with low density.

The goal is achieved by the fact that a composition comprising a resol of phenol-formaldehyde resin, modified by the cubic phenol residue by the cumene method, a surfactant, aluminum powder and a foaming curing agent, additionally contains phenol-formaldehyde resin of the elum type, as a binder, with the following ratio , ma.ch .:

Phenol formaldehyde resin, rezol type 35.1-61.3 Modified phenol formaldehyde resin and 15.3-35.1 resin

Surfactant 0,15-0,9 Aluminum powder 0,15-0,9 Foaming and curing agent 23,0-28.0

The resin, modified by the bottom condensate, is obtained by single-stage condensation of phenol, bottom residue and formaldehyde at 98-100 ° C, followed by drying at and less, and a vacuum of at least 0.75 kgf / cm. The process conditions provide a resin with a low viscosity and a high reactivity.

The binder used in the inventive composition is prepared in the following manner.

Phenol-formaldehyde resin (for example, brand FRV-iA) in accordance with the ratio given is mixed with the modified resin and stirred for 20-30 minutes at 25-40 C.

In the process of combining the resins, an additional interaction of the components of the bottom residue with the phenol-formaldehyde resin occurs. The components of the VAT residue; 1 have a plasticizing effect on the resin, which contributes to the formation of a more regular structure of the foam on its base. .

Table 1 presents the properties of the prototype binder and the proposed

Viscosity according to VZ-1, s Viscosity according to VP / X 500-3500 mPa-s (cP) Mass fraction of nonvolatile substances,% Foaming multiplicity Induction period 100-300 foaming, s

As a surfactant 60, the composition contains a sieve, a non-ionic surface-active agent, OP-7 or OP-10; as a foaming-curing agent, the product VAG-3, obtained by condensation

Table 1

sations. sulfophenol urea with formaldehyde mixed with phosphoric acid.

Table 2 presents examples of the formulations of the proposed composition in comparison with the known. 086 1015 70.1 66.5 67.6 67.5 -23.5 20 100 125 40 150

Components

Foe formaldehyde resin eeolnogo type.

Modified phenol formaldehyde resin

Surface-active substance OP-7 or OH-10

Aluminum Powder Product VAG-3 The process for preparing the foam 25 is as follows. . . The components, weighed according to the recipe, are mixed in the mixer for 30-40 s, then poured into the form, where 30 foaming and curing takes place. . IndicatorsPenoplast N Proposed Density in a dry condition, kg / m30 40 Compressive strength at 10% linear deformation, kgf / cm 0.78 1.10 Sorbtiool humidity,%. .13, .8 12.8

As can be seen from Table 3, the proposed composition provides low density foam, while its strength is high. So, for a foam plastic with a pilot 60 kg / material, the strength increases 1.6 times.

New properties of foam allow to expand its area of application. The proposed composition is used as a heat insulator when laying the pipeline more progressiveTable 2

Content of components, ma.ch. in compositions

Offered

Known

i: j ::; :: j :: i

(prototype

61.3 48.7 41.8 35.1

24.4 31.3 35.1

69-81

0.7

0.7 0.9

2.4-3.3

0.7

0.7 0.9 0.4-1.8

25.5

25.5 28.0

14.8-25.0 - -------- 1-. 2

in a channelless manner, as well as in the production of light wall structures.

Claims (3)

1. GOST 22546-77. 2. TU 6-05-1623-78. 3. Author's certificate of the USSR 2566437, cl. C 08 L 61/14, 1978 (prototype).