| The development of new materials with desirable mechanical properties is of great significance in rotational molding industry. This thesis aims at studying the potential application in rotomolding of two types of new materials: ethylene-α-olefin copolymers, or polyolefin plastomers (POPs), and thermoplastic olefin blends (TPOs) containing polypropylene and POPs. Following a thorough evaluation of thermorheological properties and sintering characteristics of these polymers, parts rotomolded in a lab scale clamshell machine were evaluated.; It was demonstrated that POPs can be rotationally molded successfully, leading to parts with excellent flexibility, impact properties, and part appearance. Incorporation of higher amounts of comonomer, leading to lower crystallinity and higher melt elasticity, resulted in slower sintering and densification rates and presence of higher amounts of bubbles in final parts.; Blends of polypropylene with POPs can be rotomolded successfully, offering excellent ductility and impact energy.; The effects of particulate form and surface treatment were also investigated. (Abstract shortened by UMI.)... |
