摘要:
Provided is a high-performance PVA fiber and its production.Each filament of the PVA fiber of the present invention having a structure comprising an aggregate of substantially innumerable fibrils, the fiber has high strength, elastic modulus, and resistances to fatigue, hot water and chemicals and can be pulpified while keeping its excellent features such as high strength. The PVA fiber of the present invention cannot, even drawn to a high ratio, be readily whitened by virtue of its fibril-aggregate structure, and can hence be made still higher in performances. The PVA fiber can be obtained by adding to a PVA solution a relatively large amount of surface active agent, and wet or dry-jet-wet spinning the thus prepared dope solution into an aqueous alkaline coagulating bath.
摘要:
A water-soluble film, comprising 100 parts by weight of (A) a sulfonic acid group modified polyvinyl alcohol and 0.05-20 parts by weight of (B) gallic acid, salts thereof or a C.sub.1-5 alkyl ester thereof.
摘要:
Provided are water soluble films comprising a modified polyvinyl alcohol containing 2-pyrrolidone ring. The films have excellent water solubility, which can be maintained over a long period of time and under the condition of being contacted with an alkaline or acid substance, and at the same time have an appropriate touch and flexibility.
摘要:
A heat-sensitive recording material with a heat-sensitive recording layer comprising a modified polyvinyl alcohol containing 2.5 to 8 mole % of a carboxyl group-containing monomer units and having a degree of saponification of 40 to 65 mole % and a viscosity average degree of polymerization. of 50 to 500; a dispersing agent comprising the above modified polyvinyl alcohol for heat-sensitive dyes or color developing agents that can make the heat-sensitive dyes form color upon heating; and a process for producing aqueous dispersions which comprises dispersing a heat-sensitive dye or a color developing agent that can make the heat-sensitive dye form color upon heating, in an aqueous medium with a dispersing agent of the above modified polyvinyl alcohol. The aqueous dispersion obtained, having excellent applicability to the surface of the base paper upon preparation of heat-sensitive recording papers and containing dispersoids of a heat-sensitive dye and a color developing agent dispersed in fine particles, can produce heat-sensitive recording materials having markedly high resolution.
摘要:
A size for yarn which minimizes thread break is described. The size comprises an aqueous solution of (I) a polyvinyl alcohol resin, (II) a modified starch, and a water-soluble cellulose compound (III), wherein the components are related by the following equations:(I)/(II)+(III))=85/15 to 95/5, and(II)/(III)=20/80 to 80/20,while simultaneously satisfying the expressions0.27X-0.7.ltoreq.log.sub.10 Y.ltoreq.0.27X+0.6; and (1)20.ltoreq.Y.ltoreq.300; (2)(A)/(B).ltoreq.0.5 (3)where X is the solid concentration in % by weight, Y is viscosity in centipoise at 90.degree. C. and a shear rate of 10 sec.sup.-1, (A) is viscosity at 60.degree. C. and a shear rate of 10,000 sec.sup.-1 of an adjusted aqueous solution resulting from the adjustment of the viscosity to 100 centipoise at 60.degree. C. and a shear rate of 10 sec.sup.-1 with said compound ratio of each of the components kept constant, and (B) is viscosity of 100 centipoise at 60.degree. C. and a shear rate of 10 sec.sup.-1 of said adjusted aqueous solution. The said aqueous solution is stuck to the yarn in an amount of 3 to 12% by weight based on the bone-dry weight thereof.
摘要:
A water-absorbing laminate comprising a water-absorbing film and a non-woven fabric, in which the water-absorbing film is formed by film-forming a mixture of (A) a water-soluble polymer containing, as the monomer component, at least 40 mole % of an .alpha.,.beta.-unsaturated compound containing one or two carboxyl groups or groups from which a carboxyl group can be easily derived and in which 5% to 50% of the carboxyl groups and/or groups from which a carboxyl group can be easily derived are in the form of a salt, and (B) polyvinyl alcohol in a weight ratio of (A)/(B) of not less than 1/99 to less than 1/9. This water-absorbing can be produced by laminating the water-absorbing film on the non-woven fabric under pressure either in a hydrous and heat-softened state of the film or through an adhesive and, optionally, heat-treating the resultant laminate.This water-absorbing laminate can avoid the formation of excessive moisture and prevent waterdrops from dropping while keeping the heat-retaining properties, when used as a sheet for a cover culture. As a result, the occurrence of disease in the plants under culture and any reduction in the yield and quality of the plants are effectively prevented.
摘要:
A water absorbing composite comprises an inorganic powder, and a highly absorbent resin covering the whole surfaces of the individual particles of the inorganic powder. The resin is obtained by reacting with a basic substance a polymer containing as a monomeric constituent an .alpha.,.beta.-unsaturated compound having in its molecule one or two carboxyl groups, or one or two other groups convertible to a carboxyl group or groups, and by crosslinking the reaction product with a polyamine. The composite is useful as a water retaining agent for agriculture and horticulture, or as a dehydrating agent for oil.
摘要:
Disclosed herein is a polyvinyl alcohol shaped article which comprises a polyvinyl alcohol (A) and rubber particles (B), said rubber particles (B) comprising a rubber component having a glass transition temperature of 5.degree. C. or less and an average particle diameter of 5 .mu.m or less and a polyvinyl alcohol (C) being bonded to the surface of said rubber component, with the weight ratio of said rubber component on the basis of the total weight of said polyvinyl alcohols being in the range of 0.03 to 2. The polyvinyl alcohol shaped article of the present invention has a high impact strength at low temperatures and in low humidity, and also has a high strength and Young's modulus in high humidity, and has an excellent appearance.
摘要:
There is disclosed an emulsion composition which comprises an aqueous emulsion (A) obtained by emulsion polymerization of 100 parts by weight of an ethylenically unsaturated monomer in the presence of 1 to 15 parts by weight of a carboxyl group-modified polyvinyl alcohol such as itaconic acid-modified polyvinyl alcohol as the dispersant and a polyamide resin (B) such as polyamide epichlorohydrin. The above emulsion composition has a long pot-life and can easily be made into a film having a high wet strength and being excellent in water resistance, hot water resistance and heat resistance. Accordingly, it can effectively be utilized in a variety of applications including paint coating, adhesive, fiber sizing agent and paper coating.
摘要:
A highly absorbent resin which is essentially a polyamine-crosslinked, partial neutralization product obtained by reaction of an alkali metal hydroxide with a carboxyl-containing polymer selected from the froup consisting of alpha-olefin-maleic anhydride copolymers, vinyl compound-maleic anhydride copolymers, polyacrylic acid, polymethacrylic acid, and mixtures thereof, the degree of neutralization of the said neutralization product being 0.4 to 0.8 equivalent of total carboxyl groups of the said carboxyl-containing polymer, the amount of polyamine as a crosslinking agent being not more than 2 parts by weight per 100 parts by weight of the neutralization product on the uncrosslinked basis, the resin being capable of absorbing at least 20 times its own weight of distilled water. The resin has good resistance to heat and good durability in the hydrous condition.