EFFECT OF POLYUINYLMETHYL ETHER UPON SYNTHETIC PQLYSTYRENE LATICES

ABSTRACT

Polyvinylmethyl ether (PUHE) does not impart significant heat-sensitivity to carboxylate-statailised synthetic polystyrene (PS) latices. It can, however, thicken and colloidally destabilise this type of latex under appropriate conditions. Results are presented for the effects of the following variables upon these phenomena: pH and polymer content of the latex, molecular weight of PUNE, presence of zinc oxide, extent of coverage of latex particles with stabiliser, addition of inorganic electrolytes, and latex particle size. The results indicate that the pronounced thickening and colloidal destabilisation which can sometimes occur are consequences of the adsorption of PUHE molecules at the surface of the latex particles. Interparticle bridging by adsorbed PUNE may also be important.