SYNOPSISThree series of polyether polyurethaneurea ( PEUU) elastomers based on poly-(tetramethylene glycol) (PTMG, MW = 1000 or 2000), 4,4'-diphenylmethane &isocyanate (MDI ) , and three kinds of diamine chain extenders, i.e., 4,4'-diaminodiphenylmethane ( DAM ) , rn-phenylenediamine ( MPD ) , and p -phenylenediamine ( PPD ) were synthesized in dimethylformamide or DMF-LiCl solvent by the prepolymer method. The degree of phase separation was higher in the samples with PTMG-2000 than in those with PTMG-1000. Three-dimensional hydrogen bonding between hard segments led to strong harddomain cohesion, but solubilized soft segment and the remaining LiCl within hard domains interfered with microstructural ordering of hard segments. According to the TG/DTA analyses, as-cast PEUU elastomers showed two-stage degradation behavior at a heating rate of 20°C /min in a nitrogen atmosphere. Initial degradation temperature was closely related with both hard-segment content and microstructural ordering, i.e., most of the hard segments were degraded in the first stage and samples with less ordered hard segments degraded at a lower temperatures.

A water-soluble chitosan derivative of N-(2-hydroxy)propyl-3-trimethylammonium chitosan chloride (HTCC), synthesized by the reaction of chitosan and glycidyltrimethyl ammonium chloride, and polyacrylonitrile (PAN) were blended using 46% (w/w) NaSCN aqueous solution as a common solvent. The total polymer concentration of blend solution was fixed at 12% (w/w), and the relative composition of PAN/HTCC in the blend solution varied from 0/100 to 80/20 by weight. The PAN/HTCC blend fibers with the appropriate physical property were prepared by a wet spinning and drawing process. The effect of HTCC content on the structural change, miscibility, and ability to be dyed of the blend fibers was investigated. The optical and scanning electron microscopic observation gave no indication of phase separation up to 20% HTCC content. Differential scanning calorimetry and dynamic mechanical measurements of the blend fibers show single glass transition temperatures that increase with increasing blend ratio of HTCC. All the experimental results exhibit that the blends are miscible on the molecular scale. The blend fibers could be dyed with an acid dye. This enhanced ability of the blend fibers to be dyed with acid dyes could be useful for one-step dyeing when mixed with other fibers, such as wool and nylon.

SynopsisPET film treated with PEG-diamine at 130°C was investigated for the aminolysis reaction and the pseudografted PEG content was measured with FTNMR. The hydrophilic properties of the PET film and fabric treated with PEG-diamine were estimated by their surface free energies, water-wicking time, oily soil releasing, and static electricity. Results obtained indicated that the PEG unit was pseudografted to the PET chain end as a result of the aminolysis reaction of the ester bond of PET by the primary amine radical of PEG-diamine. The pseudografted PET content increased with the aminolysis time [PEG wt B = 2.1147 X t (h)0.4593]. yg increased very much, y i decreased a little, and consequently ys, Z : , , and the work of adhesion of water W, increased with the increasing PEG content. yFw decreased very much, yFo increased a little, and consequently the difference between adhesion tensions of oily soil and water to the specimen (A, -A F w ) increased as the PEG content increased. The contact angle of oily soil to the specimen 8, immersed in water increased and consequently 8 , and WF0,, decreased. Therefore, the P E T fabric treated with PEG-diamine had very good water-wicking, oily soil releasing, and antistatic properties. EXPERIMENTAL MaterialThe biaxially drawn PET film, whose thickness and intrinsic viscosity are 24 pm and 0.8988, respectively, was used. It was kindly supplied from Sun

SynopsisThe aminolysis mechanism and morphological change were investigated with NMR, IR, GPC, density, and other physicochemical methods when the biaxially drawn P E T f i l m was aminolyzed with PEG-diamine at 130°C. By the aminolysis reaction, the PET chain end was capped with PEG chain as the following equation:Molecular weight showed a rapid decreasing tendency in the initial stages of the aminolysis reaction. The crystallinity, measured by density and IR methods, increased with the reaction time mainly due to the recrystallization of the amorphous PET chain promoted by better chain mobility of the PEG-terminated PET. The fold period of the chain-folded lamellar crystal formed through recrystallization was the same as that of the original P E T lamellar crystal. It was found that 74% of all the capped PEG chains were located in the amorphous region, 18.4% at the initial point from which the recrystallized lamellar crystal began to grow, and the rest in the lamellar crystalline lattice.

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