Accession Number : AD0486287

Title :   THE EFFECTS OF INTERMOLECULAR FORCES ON POLYMER RHEOLOGY. III. IONIC FORCES ABOVE TG.

Descriptive Note : Research rept.,

Corporate Author : POLYTECHNIC INST OF BROOKLYN NY DEPT OF AEROSPACE ENGINEERING AND APPLIED MEC HANICS

Personal Author(s) : Otocka, Edward P. ; Eirich, Frederick R.

Report Date : MAY 1966

Pagination or Media Count : 44

Abstract : In an effort to determine the effects of ionic interactions on the physical properties of polymers, two series of butadiene copolymers were tested for stress strain and stress relaxation behavior. The first group of copolymers were those of butadiene and methacrylic acid which were converted to their anionic form by titration with LiOCH3. The second series were copolymers with 2-methyl, 5-vinyl pyridine which were reacted with CH3I to form the polycations. Finally stoichiometric mixed polysalts were prepared by mixing solutions of the oppositely charged polyions. The modulus-temperature currves of the various materials showed relatively stable plateau values over moderate temperature spans. Both the pyridinium copolymers and the mixed polysalts showed sharp decreases in modulus over a narrow temperature range. This unusual behavior was confirmed in the stress relaxation tests, being manifested as a rapid increase in the shift factors and E(visc), the activation energy for viscous flow. The patterns indicate a transition of one form or another but whether it is indicative of the onset of ionic interchange is not clear. (Author)

Descriptors :   (*ELASTOMERS, PHYSICAL PROPERTIES), MOLECULAR ROTATION, SALTS, STRESSES, STRAIN(MECHANICS), RELAXATION TIME, INFRARED SPECTRA, BUTADIENES, ACRYLIC RESINS, ION EXCHANGE, SULFIDES, AGING(MATERIALS), ELECTROLYTES, PURIFICATION, VOLUMETRIC ANALYSIS, SOLVENTS, CALORIMETRY, FILMS, TENSILE PROPERTIES, ENTHALPY, LITHIUM COMPOUNDS, PYRIDINES.

Subject Categories : Polymer Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE