Polydimethylsiloxane is known as dimethicone in the cosmetics world. the way to get thicker dimethicone is to do what perry said and buy a thicker grade. the thickness of dimethicone depends on how the silicone polymer is structured. im unsure of how it works in the industrial fluid setting but in cosmetics you purchase dimethicone by the cSt, which is a measure of how thick it is. dimethicone can vary from 2 cst, incredibly thin, to 1,000,000,000 cSt and even above, really thick. there should be a given cSt in the paperwork somewhere, if not on the label or in the name itself. your supplier should have a thicker option.