Date of Award
Master of Science in Chemical Engineering - (M.S.)
Chemical Engineering and Chemistry
Cyril E. Geacintov
Werner J. Wenisch
William H. Snyder
The properties of TPX-RT-D30 (4-methyl-pentene-1 polymer) have been changed by blending petroleum jelly with the polymer. The polymer was blended in a Brabender apparatus with up to 40% by weight petroleum jelly (P.J.) at 270°C, pressed and quenched in water. Samples were die cut for the various tests. The polymer tensile properties (ASTM-638-64T) showed both a break and yield value in all ratios as compared to only a break value for the TPX-RT polymer. Breaking strength ranged from 4000 psi for pure TPX-RT down to 1000 psi at 40% P.J., with a leveling point of 2000 psi at 15% P.J. Yield strength formed a more uniform decrease to a low value of 1000 psi at 40% P.J. The samples had a "necking down" effect at 10% P.J. and elongation ranged from 19% for TPX-RT-D30 to 325% at 30% P.J. Modulus decreased from 1.8x105 (literature value 2.1x105) to 2.3x104 at 40% P.J. Brittle point values varied from above room temperature to 5°C at 40% P.J. The Vicat softening point (ASTM 1525 Procedure A) ranged from 181°C (TPX-RT-D30) to 87°C at 40% P.J. with a break in the curve at 154°C for 15% P.J. Differential thermal analysis (Stone) showed a melting point depression from 235°C to 218°C at 40% P.J. The electrical properties remained excellent. The material was clear up to 30% and opaque at higher ratios.
The plasticization of TPX-RT-D30 by the petroleum jelly apparently allows the high molecular weight polymer to crystallize and must influence the polymer crystalline size and perfection. Lamellar thickness may also be changed. The petroleum jelly lowers the intermolecular forces in the polymer and enables the molecules to rearrange under stress. The ability of the crystalline material within the polymer to rearrange is demonstrated in the blends by the occurrence of a yield point with its subsequent increase in elongation.
McCann, Joseph P., "The plasticization of 4-methyl-pentene-1 (TPX-RT-D30) polymer with petroleum jelly" (1968). Theses. 2092.