Abstract: A process for preparing carbon fibers of high strength which includes the steps of homopolymerizing acrylonitrile or copolymerizing acrylonitrile with other vinyl monomers in a concentrated zinc chloride aqeuous solution containing 0.01-5% by weight of hydrogen chloride to form a polymeric solution which is spinned to form precursor filaments which are carbonized to provide carbon fibers.

Abstract: A composition comprising an intimate mixture of a segmented thermoplastic polyester copolymer and at least one polyolefin. This composition is improved in recovery from creep at high temperature as well as in ease of hot cutting and adhesion.

Abstract: A polyester-polyether block copolymer composition being very stable even in the presence of heavy metals, which comprises a polyester-polyether block copolymer consisting of segments of polyester units and segments of polyether units; at least one compound containing the group of the following formula: ##STR1## wherein X is oxygen or sulfur, R.sub.1, R.sub.2 and R.sub.3 are each hydrogen or an organic residue, or R.sub.2 and R.sub.3 forms a Schiff's base with the adjacent nitrogen, and R.sub.4 and R.sub.5 are each hydrogen or an organic residue; at least one radical scavenger and/or at least one peroxide decomposer.

Abstract: A fire retardant thermoplastic polyester type block copolymer composition, which comprises (a) a thermoplastic polyester type block copolymer comprising a hard polyester segment having a high melting point and a soft polymer segment having a low melting point and a molecular weight of 400 to 6,000 and (b) a mixture of one or more kinds of halogenated bisphenyl compounds and an organic or inorganic antimony compound in a ratio of 1:0 to 1:3 by weight, and optionally one or more kinds of alkylphenol derivatives and/or an epoxy compound having 1 to 20 % by weight of oxirane oxygen.

Abstract: An electrothermally deformable levelling pad utilizable in padding, levelling or aligning girders, rails or any other constructional or structural elements. The levelling pad comprises at least one thermoplastic plate member and an electric heater for heating the thermoplastic plate member to soften or melt to cause the overall thickness of the pad to reduce to a value sufficient to bring an article or machine to a predetermined level. The plate member is made of a thermoplastic random-copolymerized polyester which comprises an acid component and a glycol component.