Thermoplastic injection moulding materials with low deformation and isotropic shrinkage properties,

摘要

Reinforced thermoplastic synthetic materials for moulded articles, having isotropic shrinkage and v. low deformation, contain at least one thermoplastic polymer (A) and hydrophilic silicate (B) in the form of compact, massive, non-crystalline, internal pore-free, spherical particles with a size of 0.5-10 microns and a BET surface area less than 50 m2/g. Also claimed are (i) the prepn. of isotropic shrinkage and v. low deformation moulded articles and (ii) injection moulded articles from the above materials. Pref. (B) are prepd. by separately heating steam and gaseous SiCl4 to 300-400 deg C and mixing in a H2O to SiCl4 mol. ratio of 2-8:1, then passing the gaseous reaction mixt. through a narrow pipe heated to 600-1200 deg C, and then through a second pipe heated to 600-1000 (700-800) deg C at a min. water column vacuum of 100 mm for a dwell time greater than 5 (9) s, with the reaction prod. being sepd. from the reaction exhaust gases. (A) is chosen from HDPE, LDPE, polypropylene, polystyrene, PVC, ABS, polyamide, polyoxymethylene (POM), TPU, polysulphone (PSU) and/or polyether sulphone (PES), pref. POM, and most pref. a blend of POM and TPU.