amp f spon 1995 experimentally the addition of about 5 wt to about 15 wt portland cement to recycled pet has been found to greatly enhance the toughness and modulus of the polymer filler material in the form of particulate portland cement has been added to melts of flakes of post consumer pet derived from soft drink bottles the portland cement had an average particle size of less than about 100 u03bcm to facilitate uniform distribution especially at higher cement levels specifically when about 5 wt to about 15 wt portland type ii cement was added to the recycled pet flakes and melts of the pet cement material were injection molded the final material was found to be noticeably tougher and more resilient to impact it was generally shown that the greater the percentage of cement the greater the realized toughness at no more than about 15 wt most of the cement stuck to the surface of the pet flakes resulting in a fairly homogenous melt and injection molded material however it was shown to be difficult to add more than about 15 wt cement to the pet flakes because the cement appeared to separate from the flakes resulting in a non homogenous melt and injection molded material also during the experimentation no steam or condensate was observed on the mold or escaping from the ram cylinder when cement was added from this observation it is believed that the cement acts as a getter absorbing much of the water.