Part I. The conductivities, electron spins, and g values of (MMn(DTO)$\sb2\rbrack\sb{\rm n}$ were determined where M = Cu(II), Ni(II), Pd(II), and Pt(II). The spin concentrations of each polymer are random comparing to the decrease of conductivities from (CuMn(DTO)$\sb2\rbrack\sb{\rm n}$ to (PtMn(DTO)$\sb2\rbrack\sb{\rm n}.$ Whereas the interchain distances increase from (CuMn(DTO)$\sb2\rbrack\sb{\rm n}$ to (PtMn(DTO)$\sb2\rbrack\sb{\rm n}$ due to the increase of atomic radii of M metals resulted in the increase of conductivities. It is concluded that the conductivities of (MMn(DTO)$\sb2\rbrack\sb{\rm n}$ polymers are greater along the interchain stacking than along the main chain. Part II. Segmented polyurethanes were prepared by reacting of soft polyol with diisocyanate to form a prepolymer then chain extended with a short chain diol to form high polymer. Stoichiometry considerations are critical for the synthesis of high molecular weight polyurethanes. Preliminary purification, drying, and molecualr weight determination of the starting materials and soft segments are extremely important. The segmented polyurethanes phase separated into hard and soft phases which was confirmed by the observation of constant glass transition temperature of each polymer system. None of the polymers showed reproducible melting transition due to the accompanied decomposition. p2BuDOP based polymers were the most acid-sensitive polymers in all five systems we studied. pAMMO/MDI/pDTM triblock copolymers with 16%, 26%, and 42% hard segment content are excellent elastomers. They showed reproducible melting transitions at maxima of $\sim$110$\sp\circ$C. The constant glass transition of each polymer indicates the polymers are phase-separated. They also showed acid-sensitivity because of the acetal structure. Rheological study showed the polymers melt at range from 50$\sp\circ$ to 120$\sp\circ$C.
| Identifer | oai:union.ndltd.org:UMASS/oai:scholarworks.umass.edu:dissertations-5778 |
| Date | 01 January 1990 |
| Creators | Lo, Huey Huey |
| Publisher | ScholarWorks@UMass Amherst |
| Source Sets | University of Massachusetts, Amherst |
| Language | English |
| Detected Language | English |
| Type | text |
| Source | Doctoral Dissertations Available from Proquest |
Page generated in 0.0135 seconds