GB942297A - Poly(4-methyl-pentene-1) and articles produced therefrom - Google Patents

Abstract

A polymer of 4-methyl-pentene-1 is prepared by polymerizing the monomer under air and moisture-free conditions in the presence of a stereospecific catalyst, and as diluent an inert hydrocarbon liquid, excess of the monomer itself or a chlorinated aromatic hydrocarbon, whereby a separable slurry of poly-4-methyl-pentene-1 is diluent is obtained and then de-ashing the polymer under water-free conditions so that the ash content does not exceed 0.1% by weight of the polymer and the transition metal content of the polymer is below 50 p.p.m. In the de-ashing operation, the slurry or its dispersed polymer content is treated with sufficient of an effective reagent to react with all of the catalyst residues to convert them to products soluble in the liquid medium, then the polymer is washed at least until all visible colour has been removed and finally the polymer is separated from the residual wash liquid. The polymer obtained has a melting point of 243 DEG C., a melt flow index between 0.01 and 1000, a density of 0.82 to 0.86 g/cc. and can be melt shaped into shaped articles having in 1/8 inch section a clarity of grade 1 and a haze of group 1. Suitable liquid media for the de-ashing step include (a) the dispersion phase of the slurry (including any unreacted reagent plus any other organic solvent which may be added), (b) if the dispersed polymer has previously been separated from the dispersion phase of the slurry, the liquid media may be any unreacted reagent plus any other organic solvent which might have been added to the polymer and any of the dispersion phase of the slurry occluded with the dispersed polymer. If the medium is primarily hydrocarbon, the higher alcohols, higher acids and higher amines (e.g. carbon chain of at least 8 carbon atoms) may be employed as the de-ashing reagents. e.g. 3,5,5-trimethylhexanol dodecanol, n-nonoic acid and 3,5,5-trimethylhexylamine may be used. Mixtures of acetyl acetone and isopropylalcohol may also be used. If the medium is primarily a polar one, lower alcohols may be used both as the reagent and as the medium. Numerous examples are given in which the stereospecific catalysts are selected from TiCl3 with AL(C2H5)2 Cl, LiC4H9, Zn(C4H9)2, AL(C2H5)3, AL(iso-C4H9)3, lithium aluminium butyl triethyl or with aluminium ethyl sesquichloride. The de-ashing agents are selected from acetylacetone with n-butanol or isopropyl alcohol; n-butanol; isopropanol; nonanol; ethanol; methanol; n-dodecanol; n-nonoic acid; 3,5,5 trimethylhexylamine; 3,5,5 trimethylhexanol and acetyl acetone. The washing medium is preferably a water-free organic liquid. In some examples, alcohols e.g. methanol, ethanol, isopropanol, butanol and nonanol, are used both as the de-ashing reagent and as the washing agent. Shaped articles may be produced from the polymers by the usual processes. Specifications 789,781, 808,144, 821,634, 877,050 and 940,145 are referred to.