IL41633A - Aminoplastic moulding compositions and their manufacture - Google Patents

Abstract

1422158 Porous filled aminoplastic compositions BRITISH INDUSTRIAL PLASTICS Ltd 5 March 1973 [4 March 1972] 10196/72 Headings C3C and C3R A thermosetting moulding composition comprises an uncured aminoplast resin having dispersed therein a filler which comprises at least in part a particulate cured unfilled aminoplast resin material having an absorbency of at least 2À0 ml. of water/gm. and being (a) in the form of a disintegrated foam or (b) formed as a precipitate from solution. In examples the filler was made from an aqueous urea-formaldehyde resin solution containing sodium alkyl benzene sulphonate, an ethylene oxide condensate of a mixture of synthetic fatty alcohols and a hardener comprising aqueous phosphoric acid or dodecyl benzene sulphonic acid, and optionally ethylene glycol: the filler was optionally neutralized with Ca(OH) 2 and ZnO, and if in foam form was then crushed or milled; the filler was then compounded with urea formaldehyde resin solution, optionally alphacellulose, and hexamethylene tetramine, zinc stearate, monocresylglyceryl ether and barium sulphate, and the foamed filler was optionally neutralized with an addition of Ca(OH) 2 to the composition. The filler may be made by foaming the resin solution before mixing the hardener solution (which may also be foamed) therewith, or alternatively, the filler may be made as a precipitate from the resin solution after addition of the hardener. [GB1422158A]

Claims (13)

1. A thermosetting moulding composition comprising a thermosetting resinous matrix having a filler dispersed through it, wherein the thermosetting resin of the resinous matrix is an amino-formaldehyde resin and the fiiler comprises at least in part an unfilled, cured amino-formaldehyde material which has an absorbency of at least 2.0 millilitres of water per gram and which (a) is in the form of a disintegrated foam or (b) has been formed as a precipitate from solution.

2. A moulding composition according to Claim 1, wherein the unfilled, cured amino-formaldehyde material is in the form of a disintegrated foam.

3. A moulding composition according to Claim 1, wherein the unfilled, cured amino-formaldehyde material has been formed as a precipitate from solution.

4. A moulding composition according to any preceding claim, wherein the filler is a mixture of the unfilled, cured amino- formaldehyde material and a cellulose filler.

5. A moulding composition according to any one of Claims 1 to 3, wherein the filler is a urea-formaldehyde material.

6. A moulding composition according to any one of Claims 1 to 4 , wherein the filler comprises from 30 to 70 percent by weight, based on the total weight of filler, of the unfilled, cured amino- formaldehyde material.

7. A moulding composition according to any one of the preceding claims, wherein the resin: filler ratio is within the range from 6:1 to 1:1.

8. A moulding composition according to Claim 1, wherein the filler is or comprises the product of any one of Examples A to 0.

9. A moulding composition substantially as hereinbefore described with reference to any one of Examples II to X.

10. A method of manufacturing a moulding composition as claimed in Claim 1, comprising a wet-mixing technique wherein a filler consisting of or including an unfilled, cured amino-formaldehyde material having an absorbency of at least 2.0 millilitres of water per gram is dispersed in a aqueous aminoplastic resin syrup.

11. A method of manufacturing a moulding composition, substantially as described in any one of Examples II to X. 41633/2 ■ - - ;

12. A moulding composition manufactured by a method according to Claim 10 or Claim 11.

13. Articles of manufacture, moulded from a moulding composition as claimed in any one of Claims 1 to 9 and 12. HE:mr