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Fukui-shi, Japan

Nakazawa Y.,Tokyo University of Agriculture and Technology | Asano A.,Japan National Defense Academy | Nakazawa C.T.,Japan National Defense Academy | Tsukatani T.,NICCA CHEMICAL Co. | Asakura T.,Tokyo University of Agriculture and Technology
Polymer Journal | Year: 2012

In this paper, we performed solid-state nuclear magnetic resonance (NMR) measurements, including T 1 H and T 1ρ, of silk fibroin (SF)/polyurethane (PU) composites to examine their possible use as a material for artificial vascular grafts. In the development of new artificial vascular grafts made from SF/PU, it is important to examine the miscibility of the composites and their molecular dynamics, because these properties are intimately involved in the resulting physical properties of the resulting vascular graft. The T 1 H measurements showed that the domain size of the SF/PU1:1 composite is smaller than the domain size of the 1:10 and 1:2 composites, indicating that the molecular miscibility between SF and PU are partially in close proximity, particularly in the SF/PU1:1 composite. Additionally, we observed that the molecular motion of the soft segment of PU in the SF/PU composites becomes slow, suggesting that the soft segment of PU interacts with SF to some extent. These analyses provided basic structural information for the development of silk-b ased artificial vascular grafts using PU. © 2012 The Society of Polymer Science, Japan (SPSJ) All rights reserved. Source


The invention provides a crystalline polyester resin obtained by condensation polymerization of a mixture comprising a polycarboxylic acid component and a polyol component, present in a range such that the ratio of the number of carboxyl groups from the polycarboxylic acid component and the number of hydroxyl groups from the polyol component is in the range of 100:108 to 100:120, and having an acid value of 5 to 20 mgKOH/g, wherein the polycarboxylic acid component includes a C8-12 aliphatic dicarboxylic acid, the content ratio of carboxyl groups from the C8-12 aliphatic dicarboxylic acid is at least 90 mol % of the total amount of carboxyl groups from the polycarboxylic acid component, the polyol component includes a C8-12 aliphatic diol, and the content ratio of hydroxyl groups from the C8-12 aliphatic diol is at least 90 mol % of the total amount of hydroxyl groups from the polyol component.


The water-and-oil repellant composition of the invention including an aqueous dispersion of a pyrazole blocked hydrophobic polyisocyanate containing a pyrazole blocked hydrophobic polyisocyanate represented by the following formula (I) and a non-ionic surface active agent, and a water-and-oil repellant component having a perfluoroalkyl group with 6 carbon atoms or less is provided: {in the formula (II), n represents an integer of from 0 to 3; if n is 1 or higher, R1, which is the same or different from each other, represents an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an N-substituted carbamyl group, a phenyl group, NO2, a halogen atom, or COOR2 (in the formula, R2 is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms)}].


Patent
Nicca Chemical Co. | Date: 2011-01-21

An oligomer removing agent for polyester-based fiber materials comprises a polyester copolymer which is obtained by polycondensation of a dibasic acid component containing 15-65 mol % of a sulfonate group-containing dibasic acid and a dihydric alcohol component containing polyethylene glycol with a molecular weight of 900-3500, and which has a 200 C. melt viscosity of 5000-23,000 mPas and has 10-40 mass % polyoxyethylene chains in the molecule. The oligomer removing agent is able to overcome the problems caused by deposition of polyester oligomers, when added to the dyeing bath in a dyeing step for polyester fiber materials or for fiber materials that are composites thereof with other fiber materials.


An amorphous polyester resin of the invention is obtained by reaction between a polyester resin (A), obtained by reaction between a polyhydric alcohol component and a first poly-carboxylic acid component, either or both including a 3 or higher valent component, and having a weight-average molecular weight of 6,000 to 40,000 and a hydroxyl value of 15 to 70 mgKOH/g, and a second poly-carboxylic acid component (a), under conditions satisfying the following equations (1), (2) and (3), and the amorphous polyester resin satisfying the following equation (4).

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