Abstract: A thermoplastic synthetic resin such as polyethylene or ethylene-vinyl acetate copolymer resin containing 0.1 to 10 wt. % of a specific additive selected from specific classes of compounds, namely saturated higher fatty acid amides, saturated higher aliphatic amines and complete esters of saturated higher fatty acids is found to be very suitable for production of expanded articles and can be easily formed into expanded articles with little shrinkage after expansion, free from creases on the surface or cracks on the cell walls, and having excellent characteristics such as good closed cellular characteristic, high compressive strength, low density, etc.

Abstract: Polyolefin foam having small, uniform cell size is prepared (1) by mixing a polyolefin resin with (a) a volatile organic blowing agent and (b) from about 0.1 to about 5 weight percent, based upon the polyolefin resin weight, of a cell control agent (e.g., such as amorphous silica having a pH of from 3.5 to 4.5), said cell control agent being in the form of nonporous microspheres having an average particle size of from about 5 to about 100 m.mu. and (2) by thereafter extrusion-expanding the resultant mixture.

Abstract: The invention relates to a foaming on foamable olefin polymer composition containing a nucleating agent and a cell size increasing agent comprising certain amino acids and/or polyhydric alcohols.

Abstract: A thermoplastic synthetic resin such as polyethylene or ethylene-vinyl acetate copolymer resin containing 0.1 to 10 wt. % of a specific additive selected from specific classes of compounds, namely saturated higher fatty acid amides, saturated higher aliphatic amines and complete esters of saturated higher fatty acids is found to be very suitable for production of expanded articles and can be easily formed into expanded articles with little shrinkage after expansion, free from creases on the surface or cracks on the cell walls, and having excellent characteristics such as good closed cellular characteristic, higher compressive strength, low density, etc.

Abstract: An extrusion foamed article with a large cross-sectional area is made by extrusion foaming a mixture of an ionomer resin and a styrenic resin utilizing a volatile blowing agent. The process permits economic production of a novel thick, foamed article having well balanced properties.

Abstract: Foamed thermoplastic mixture of ionomers and polyolefin polymers are produced by extruding the mix together with a volatile blowing agent at elevated temperature and pressure. The density of the foamed products is from of 15 to 45 Kg/m.sup.3 and they satisfy the requirements of extrusion foamability, compressive strength or rigidity, thermal resistance and adhesion properties.

Abstract: A thermoplastic synthetic resin such as polyethylene or ethylene-vinyl acetate copolymer resin containing 0.1 to 10 wt. % of a specific additive selected from specific classes of compounds, namely saturated higher fatty acid amides, saturated higher aliphatic amines and complete esters of saturated higher fatty acids is found to be very suitable for production of expanded articles and can be easily formed into expanded articles with little shrinkage after expansion, free from creases on the surface or cracks on the cell walls, and having excellent characteristics such as good closed cellular characteristic, high compressive strength, low density, etc.