METHOD AND MEANS BY MANUFACTURE OF A PRODUCT OF EXPANDED POLYMER

摘要

The present invention is for method and means by the manufacture of a product of expanded polymer, by which is obtained a weight per unit volume which is essentially lower than that of homogeneous expanded material. The starting material for the manufacture of a product according to the invention can be either a specially manufactured starting material or scrap and recovered material. The pieces of expanded polymer are supplied in controlled quantities through a feeder (3) to a space (1) for the application of glue drops which are sprayed into the space from one or more dies (6). In the space (2) the pieces of polymer are dried by means of microwave energy which is obtained from an energy generator (9) and magnetrones (10). The dried pieces then are discarded from the space (2) together with the air flow through the opening (11). By the manufacture of a product according to the invention one starts from the pieces with glue applied to them as described above. The pieces are put into some kind of mould wherein they are pressed against each other. Thereupon the material is heated so that the glue becomes sticky and the pieces attach to each other. The heating is done by means of microwave energy which finds its way into and homogenously heats the whole volume of material. The method according to the invention makes it possible to manufacture products which retain their elasticity and have a weight per volume unit essentially lower than that of the starting material.