Reactive compounding of TPU and PVC.

To develop an abrasion-resistant material, potentially for cable jackets, tubing, and shoe soles, a reactive blend of TPU and PVC was created by preblending two monomers of TPU with PVC, then adding the third TPU monomer in a second stage. PVC is first compounded in a counter-rotating Leistritz twin-screw extruder with polyol and butanediol chain extender, which act like plasticizers. Then in barrel section live (of eight), the highly reactive MDI is added, creating a TPU/PVC blend, This method avoids the thermal degradation of melt compounding and needs no solvents. The work was done by Shane Paruell, Johanna Baena and Dr. Kyunsuku Min of the Dept. of Polymer Engineering at the Univ. of Akron, Ohio, and was reported at the SPE ANTEC in Boston in May. Tel: [phone] * www.poly-eng.uakron.edu