(65y) Continuous Solid-State Fabrication of Polymer Nanocomposites

Polymer nanocomposites are advanced materials that contain small amounts of nanoscale fillers in the polymer matrix. The physical property improvements in the resulting nanocomposites lead to a wide range of high-performance applications from packaging to automotive parts.

There are several widely-used techniques to fabricate polymer nanocomposites, each with distinct advantages and weaknesses. In situ polymerization and solution mixing require the use of external chemicals in batches, while the high temperature operation in melt mixing can lead to practical issues like polymer degradation and filler re-agglomeration.

Solid-state processing of polymer nanocomposites is a relatively novel method which applies high shear and compressive forces at temperatures below the melt and/or glass transition temperature of the polymer. Solid-state shear pulverization (SSSP) is an industrially-applicable, continuous solid-state process in which polymer/nanofiller blends are pulverized within a chilled twin-screw extruder.

This poster discusses the features of Bucknell's new solid-state pulverizing system, focusing on the screw setup and feeder design. Mechanical properties of pure polymers are investigated to gain insight into the mechanochemistry occurring in SSSP. Model polypropylene-based nanocomposites made via SSSP are compared with equivalent samples made via conventional melt-mixing processes. Various physical property measurements were conducted to evaluate the processing-structure-property relationships.