Most polymers suffer from certain problems during processing such as energy consumption and low flow rate. In addition, the polymeric products do not degrade easily in natural environment after being used. To overcome these problems polymeric material can be blended with other polymers that have the ability to improve the processability and biodegradation. This book contains: the preparation of four novel hyperbranched polyester polymers (HBPEs), by the preparation of the starting material B3 monomer and then mixing it with the four other types of materials as A2 monomer, using the polycondensation polymerization method for A2 + B3 type monomers. The prepared hyperbranched polyester polymers (HBPs) were added in different weight proportions (5%, 10%, and 20%) to both the virgin polypropylene (VPP) and the recycled polypropylene (rPP) polymer using a twin screw extruder. The mechanical, thermal, morphological, and rheological properties as well as the biodegradation in the soil environment of the prepared blends have been studied.