![]() ![]() In 2 1 (by volume) HMPA/NMP, the highest inherent viscosity polymer is obtained when each reactant is present in concentrations of ca 0.25 M higher and lower concentrations result in the formation of polymer of lower inherent viscosities. The preparation of high molecular weight PPT in HMPA/NMP shows a strong dependence of inherent viscosity on reactant concentrations. ![]() Therefore PBA of fiber-forming molecular weight can be prepared in the soHd state. ![]() PBA of inherent viscosity, 4.1 dL/g, has been obtained in a hexane slurry with pyridine as the acid acceptor. When pure needle-like crystals of -aminobenzoyl chloride are polymerized in a high temperature, nonsolvent process, or alow temperature, slurry process, polymer is obtained which maintains the needle-like appearance of monomer. A thermal stabkity of 501☌ (10% weight loss in N2) was observed. These polymers show complete solubkity in THF, chloroform, ben2ene, DMAC, DMF, and NMP, and form clear, colorless, tough films the inherent viscosity in chloroform at 25☌ is 0.8 dL/g. Ī polyester backbone with two HFIP groups (12F aromatic polyester of 12F-APE) was derived by the polycondensation of the diacid chloride of 6FDCA with bisphenol AF or bisphenol A under phase-transfer conditions (120). AH polymers begin to decompose above 370☌. These polymers are easily soluble in polar aprotic solvents with inherent viscosities in the range of 0.3-0.9 dL/g in NMP at 20☌. New heat-resistant polymers containing -iiitrophenyl- substituted quinoxaline units and imide rings as well as flexible amide groups have been synthesi2ed by polycondensation reaction of a dianainoquinoxaline derivative with diacid dichlorides (80). ĭecomposition temperatures are in the range of 360-375☌ and inherent viscosities range from 0.62 to 0.90 dL/g in cone H2SO4. These polymers show thermal stabiUty in the range 300-340☌ (10% weight loss) and inherent viscosities of 0.15-0.45 dL/g. Infringement search Infusion botanical extract Infusion mashing Infusors Ingrain Blue 2 1 Ingrain dyes Inhalation anesthetics Inherent viscosity Inhibin. (9.12) with the definition of the inherent viscosity and then expanding the logarithm. That this is the case is readily seen by combining Eq. A plot of inherent viscosity versus concentration also extrapolates to in the limit of C2 0. The inherent viscosity (I/C2) In (77/770). ![]()
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