Abstract: The present invention is to provide a drying method by which both cost reduction and superior physical properties can be attained in a step which comprises subjecting a water-containing gel-like crosslinked polymer obtained by polymerizing an aqueous monomer solution to fine granulation during or after the polymerization, and drying the resultant particulate water-containing gel-like crosslinked polymer with a through-circulation band dryer. The method has a feature in that the drying conditions over a period from a time of introducing the particulate water-containing gel-like crosslinked polymer into a drying zone of the through-circulation band dryer to a time of reaching a solid content concentration thereof to 80% by weight, satisfy that (1) a difference of temperature between a temperature of hot air blown to a particulate hydrogel layer and a temperature measured after the hot air passes through the particulate hydrogel layer is 20 to 70° C.

Abstract: A process for producing a water-absorbing polymer by polymerizing a monomer solution and drying the resulting hydrogel by means of a heated gas stream comprises effecting the drying in two or more temperature zones, and/or the gas stream is flowed against the hydrogel upwardly in the upstream sector of the belt dryer and downwardly in the downstream sector of the belt dryer, the direction of flow being reversed at a water content of 15% to 45% by weight for the hydrogel, and/or the hydrogel layer is flowed against in a belt dryer upwardly to some extent at least, the gas velocity being 5% to 30% of the gas velocity required to lift the hydrogel off the belt, also apparatus for carrying out the process and use of the water-absorbing polymers produced by the process to produce hygiene articles.

Abstract: A water absorbent resin is dried in a continuous fluidized bed having a heat transfer tube and at least two drying rooms. Pulverization is performed between a first drying room at not less than 80° C. to not more than 200° C. and a second or subsequent room at not less than 100° C. to not more than 220° C. A method for producing a water absorbent resin includes: (1) polymerizing a monomer aqueous solution; (2) drying a hydrogel polymer of step (1); (3) performing particle size control of the dry polymer of the step (2); (5) surface crosslinking the water absorbent resin powder of step (3), and step (4) of performing a second heat drying on the water absorbent resin powder of step (3), preceding step (5). The water absorbent resin has a moisture content of 0 wt % to 3 wt % before the step (5).

Abstract: The invention relates to composite polymer modifiers for thermo-plastic resins, and especially for polyvinyl chloride (PVC). The composite modifier is an intimate blend of mineral filler and polymeric process aid, which is formed by the co-powderization of aqueous emulsions, suspensions or slurries of one or more mineral filler(s) and process aid(s). The resulting composite modifier provides more effective modification of the thermoplastic resin than by the use of the dried components formed separately. The composite modifier may also contain other co-powderized components such as impact modifiers, for additional benefits.

Abstract: An inexpensive and durable polymer electrolyte composition exhibiting high ionic conductivity even in the absence of water or a solvent, characterized by comprising a molten salt and an aromatic polymer having a carbonyl bond and/or a sulfonyl bond in the main chain thereof and containing a cation exchange group. The aromatic polymer is preferably an aromatic polyether sulfone having a specific structural unit and containing a cation exchange group, an aromatic polyether ketone having a specific structural unit and containing a cation exchange group, or an aromatic polyether sulfone block copolymer and/or an aromatic polyether ketone block copolymer, the block copolymers comprising a hydrophilic segment containing a cation exchange group and a cation exchange group-free hydrophobic segment. The polymer electrolyte composition containing the block copolymer as an aromatic polymer exhibits high structural retention even in high temperatures.

Abstract: An inexpensive and durable polyelectrolyte composition includes both an aromatic polymer containing carbonyl linkages and/or sulfonyl linkages in the backbone chain and bearing cation-exchange groups and a fused salt exhibits a high ionic conductivity even in the absence of water or a solvent. The aromatic polymer is preferably an aromatic polyether sulfone comprising specific structural units and bearing cation-exchange groups, an aromatic polyether ketone comprising specific structural units and bearing cation-exchange groups, an aromatic polyether sulfone block copolymer consisting of at least one hydrophilic segment bearing cation-exchange groups and at least one hydrophobic segment free from cation-exchange groups, and/or an aromatic polyether ketone block copolymer consisting of at least one hydrophilic segment bearing cation-exchange groups and at least one hydrophobic segment free from cation-exchange groups.

Abstract: A fluororesin powder coating composition having high light resistance and being excellent in blocking resistance and smoothness of the coating film when coated, and a fluororesin powder to be used for a powder coating material, are presented. The fluororesin powder coating composition is made by using as the main material resin a composite fluorinated copolymer powder having a core/shell structure wherein core particles are made of a fluorinated copolymer and their surfaces are covered by e.g. a (meth)acrylate resin having a glass transition temperature higher than that of the core particles. The core/shell structure is formed by seed polymerization wherein fluorinated polymer particles are used as seeds.

Abstract: Emulsion polymers useful in the preparation of coatings and adhesives, including PSA tapes, labels, and other constructions, are provided. The polymers are characterized by high solids content and low viscosity. A method of making the polymers is also provided. A plurality of acrylic monomers are copolymerized in the presence of a plurality of surfactants, using a split feed, and the resulting emulsion polymers have a bimodal or higher particle-size distribution.

Abstract: The biocompatibility of various polymers are improved by blending with them a polymer including a zwitterionic group. The zwitterionic group is usually an ammonium phosphate ester zwitterionic group and the polymer containing it may be produced by the free radical polymerisation of ethylenically unsaturated monomers including a monomer bearing the zwitterionic group. Blending of the two polymers may be achieved by dry blending particulate polymers or by mixing the polymers in liquid dispersion or solution followed by removal of the liquid medium. The fibrinogen absorption and/or platelet activation of polymers may be reduced to a value of less than 80% or even less than 60% of the base polymer by introducing amounts of more than 10% or more than 30% of the zwitterionic group containing polymer. Preferred blends are of copolymers of 2-(methacryloyloxyethyl)-2′-(trimethylammonium)ethyl phosphate inner salt with higher alkyl(meth)acrylate, blended with olefin polymers and/or with rubber latices.

Abstract: A polymer is formed from monomers including a zwitterionic monomer, a cationic monomer and a hydrophobic termonomer. The polymer may be cross-linkable. The polymer may be coated onto a surface from a liquid coating composition followed by contacting the coated surface with heparin. The double coated substrates have improved heparin activity over extended periods as compared to heparinised surfaces which are commercially available. Other anionically charged mucopolysaccharides may be used. The polymers may also scavenge heparin from treated blood to avoid use of potentially toxic heparin inhibitors. Preferably the terpolymer is formed from 2-methacryloyloxyethyl-2-(trimethylamonium)phosphate inner salt, choline methacrylate and n-dodecyl methacrylate.

Abstract: Disclosed is a polymer blend composition and shaped article, and a process of blending and making shaped articles of polymer blends in which the biocompatibility of various polymers is improved by blending with them a polymer including a zwitterionic group. The zwitterionic group is usually an ammonium phosphate ester, preferably a choline, zwitterionic group and the polymer containing it may be produced by the free radical polymerization of ethylenically unsaturated monomers including a monomer bearing the zwitterionic group. Blending of the two polymers may be achieved by dry blending particulate polymers or by mixing the polymers in liquid dispersion or solution followed by removal of the liquid medium. The fibrinogen absorption and/or platelet activation of polymers may be reduced to a value of less than 80% or even less than 60% of the base polymer by introducing amounts of more than 10% or more than 30% of the zwitterionic group containing polymer.

Abstract: Method of producing dry polyvinyl acetate particles that are readily dispersible in water, are vinyl acetate monomer free and are useful for making polyvinyl acetate dispersion compositions that are low in odor, form clear dried films and may be used in adhesives, sealants, caulks and coatings. The method includes manufacturing an aqueous, e.g. water, dispersion of polyvinyl acetate containing polyvinyl alcohol; drying to remove volatiles by converting the dispersion to dry form under controlled temperature conditions and redispersing the dried polyvinyl acetate particles in an aqueous medium to form a polyvinyl acetate dispersion that is substantially free of vinyl acetate monomer.

Abstract: The invention concerns a process for preparing coating powder compositions in which one or a plurality of base resins and one or a plurality of hardeners, each of which is in solid form, is dissolved with a low-molecular compound above its critical pressure and critical temperature. This low-molecular compound is inert with respect to the base resins and hardeners and is in gaseous form under normal operating conditions with respect to pressure and temperature. The pressure of the resultant solution is then reduced, for example, by spraying. The resultant coating powder composition can be sprayed directly onto a substrate to be coated. Coating powders can also be recycled according to the process of the invention.

Abstract: A system for preparing oriented block copolymer structures includes a copolymer solution, a device capable of providing a flow field and an evaporation device. The device can be at least two cylinders that are parallel and adjacent to one another to form a nip and a driving mechanism to rotate each cylinder. Means for controlling a solvent environment and evaporation are provided.

Abstract: The use of falling-film evaporation and a concentration means such as centrifugal separation to dehydrate and concentrate a water-in-oil polymer emulsion or suspension is disclosed. In a preferred embodiment, a water-in-oil polymer composition containing less than about 25% active polymer solids is dehydrated in falling-film evaporator to produce an evaporator concentrate containing less than about 5.0% water. The evaporator concentrate then flows to a separation device such as a centrifuge, wherein oil is removed to produce a composition that is substantially a polymer and emulsifying surfactant-in-oil composition containing in excess of about 60 weight % polymer solids. The centrifuge raffinate may optionally be treated in a second separation means to capture additional polymer solids, with optional recycle of the oil-rich raffinate. The concentrated polymer composition is preferably stabilized with a steric stabilizer to produce a free flowing liquid product.

Abstract: The use of falling-film evaporation and a concentration means such as centrifugal separation to dehydrate and concentrate a water-in-oil polymer emulsion or suspension is disclosed. In a preferred embodiment, a water-in-oil polymer composition containing less than about 25% active polymer solids is dehydrated in falling-film evaporator to produce an evaporator concentrate containing less than about 5.0% water. The evaporator concentrate then flows to a separation device such as a centrifuge, wherein oil is removed to produce a composition that is substantially a polymer and emulsifying surfactant-in-oil composition containing in excess of about 60 weight % polymer solids. The centrifuge raffinate may optionally be treated in a second separation means to capture additional polymer solids, with optional recycle of the oil-rich raffinate. The concentrated polymer composition is preferably stabilized with a steric stabilizer to produce a free flowing liquid product.

Abstract: A process for the manufacture of a solid urea-formaldehyde resin comprises steps (a) to (d). Step (a), the initial reaction step is carried out under specified conditions with an F:U ratio of at least 2.5 to 1. The F:U ratio is lowered by addition of urea in step (c) and water is evaporated without precipitation of the resin in step (d).

Abstract: There is disclosed a process for the production of a pigment-synthetic resin concentrate containing an organic solvent soluble polymer and carbon black having quicker distributability in organic media such as lacquer binding media, printing inks, etc., such concentrates being especially suitable for the production of molded parts, castings, films and/or synthetic fibers, the process comprising continuously homogenizing in a mixer powdery pigment and powdery synthetic resin jointly with an organic solvent in a given case also containing plasticizer, stabilizer and/or dispersing acid, dispersing the pigment in the mixture, removing the solvent from the dispersion, comminuting the resulting pigment-synthetic resin concentrated and grinding the product.