Yoshiyuki Sano

Studies on regenerated protein fibers. III. Production of regenerated silk fibroin fiber by the self‐dialyzing wet spinning method

The spinnable dope containing 20 wt % of silk fibroin dissolved in the MU solvent (e.g., LiBr · H2O = 40 wt %, and EtOH : H2O = 100 : 0 in volume) was spun into a coagulant and subsequently drawn, to give the following results. 1 Methanol, ethanol, and isopropanol were a predominant coagulant for the dope, and the coagulant containing 10% LiBr · H2O is best. 2 Spinnability depended upon the ratio of nozzle hole length to diameter (L/D) and was improved by increasing L/D from 4 to 10. Coagulativity was not sufficient at the SF concentration of 16%, but improved by raising it up to 20%. Drawability of the spun filaments in water was improved at a temperature above 60°C. 3 The drawn fiber showed excellent mechanical properties, especially tensile toughness when as-spun fiber was drawn in water at 61°C. An X-ray diffraction diagram of the drawn fibers indicated their crystalline axes were partially oriented along the fiber axis.

Synthesis of poly[(N-acylethylenimine)-b-(ethylene oxide)] and its antielectrostatic property

Abstract Block copolymers consisting of poly(N-acylethylenimine) and poly(ethylene oxide) chains were prepared by initiating the polymerization of 2-methyl-2-oxazoline (MeOZO) and 2-ethyl-2-oxazoline (EtOZO) with α,ω-di-sulphonylated poly(ethylene oxide). Kinetic studies of the MeOZO polymerization with a model initiator of triethylene glycol di-methanesulphonate (MsTEG) have shown that the polymerization proceeded with slow initiation and rapid propagation. It is postulated therefore that block copolymers of ABA and AB type were formed depending on the polymerization conditions. Blends of the block copolymers (3 wt%) with Nylon 6 were spun to fibre which showed good anti-electrostatic property.

N-acetylpolyethylenimine: A blending agent for polyamide fiber

SummaryThis paper describes a blending agent N-acetylpolyethylenimine(AcPEI) for polyamide fiber. Two types of AcPEI were examined; the branched one which was the acetylated product of commercial polyethylenimine(PEI) and the linear one prepared by the ring-opening polymerization of 2-methyl-2-oxazoline. Polyamide fibers(nylon 6) blended with a 2–10 wt % ratio of AcPEI were prepared by the melt-spinning technic. The processability of spinning was very high because and were very compatible with polyamide. In addition, the polyblend fibers obtained displayed good antistatic and dyeing properties, in which containing tertiary amino groups was more effective than. The mechanical properties were also disccussed.

Zwitterions of 1-poly(oxyethylene)-2-imidazoline derivatives as anti-electrostatic agent for polyamide fiber

SummaryThis paper describes a group of anti-electrostatic agents 1 for polyamide fiber(Nylon 6). Agents 1 are calcium imidazolinium-carboxylates having poly(oxyethylene) chain and long alkyl group (C11H23 and C17H35). Eight derivatives of 1 were prepared by a four-step one-pot synthesis shown in Scheme 1. Nylon 6 fibers and films containing some of 1 (1.0 and 2.0 wt%) show improved anti-electrostatic property. The performance of 1 was increased by the increase of the length of poly(oxyethylene) chain.

Reactivity of N-alkylated cyclic imino ether salts having vinyl group

SummaryTwo copolymers of 2-isopropenyl-2-oxazolinium tetrafluoroborate with methyl methacrylate and with methyl acrylate were prepared, from which the polymerization of 2-oxazolines (2-methyl and 2-t-butyl) was initiated to prepare graft copolymers.