Abstract:
A particulate polyvinylacetal resin of low metal content, being excellent in transparency, moisture resistance and electrical resistance, and having a large specific area, and a process for producing the same. A particulate polyvinylacetal resin of 60 mol% or more acetalization degree,1.50 to 3.50 m2/g specific surface area, 0.12 to 0.19 g/cm3 bulk density, 0.5 to 2.5 mum average particle diameter and 80 ppm or less metal content is obtained by reacting polyvinyl alcohol and an aldehyde in the presence of an acid catalyst. In particular, the particulate polyvinylacetal resin is produced for example, by feeding a reaction fluid containing polyvinyl alcohol, an aldehyde and an acid catalyst into a first reactor, carrying out an acetalization reaction until an acetalization degree of 10 to 60 mol%, discharging the reaction mixture, feeding the same into a second reactor and performing further reaction until the acetalization degree of polyvinylacetal resin is 65 mol% or higher.
Abstract:
Polymer particles including a covalently bonded chemical species, as well as related compositions and methods are disclosed. In one aspect, the invention features a particle that includes a polymer a chemical species covalently bonded to the polymer. The polymer includes vinyl alcohol monomer units, and the chemical species is selected from polymers, oligomers and monomers. The particle has a maximum dimension of 5,000 microns or less. In another aspect, the invention features a particle that includes a polymer, a chemical species covalently bonded to the polymer and a therapeutic agent. The polymer includes at least five weight percent vinyl alcohol monomer units and at least five weight percent vinyl formal monomer units. The chemical species is selected from polymers, oligomers and monomers and the particle has a maximum dimension of 5,000 microns or less.
Abstract:
A stable aqueous film forming dispersion comprising: a polymer selected from the group consisting of: polyvinyl butyral, polyvinyl acetal, ethylene vinyl acetate, polyvinyl acetate and mixtures thereof; a plasticiser; an emulsifier; and a water soluble organic metallic crosslinking agent.
Abstract:
Monomers, polymers and copolymers are provided that incorporate at least one naturally occurring phenolic compound, such as a plant phenol, as well as methods for producing the monomers and polymers. Plant phenols possessing a reactive group in addition to the phenolic group, such as a double bond, aldehyde, ester, alcohol or carboxylic acid, are particularly useful. Plant phenols can be isolated from a plant material, or chemically or enzymatically synthesized.
Abstract:
Die Erfindung betrifft ein Verfahren zur Modifikation von acetalisierten Polyvinylalkoholen durch Reaktion mit Epoxiden in der Polymerschmelze und die Verwendung dieser Produkte z.B. in keramischen Anwendungen.
Abstract:
Monomers, polymers and copolymers are provided that incorporate at least one naturally occurring phenolic compound, such as a plant phenol, as well as methods for producing the monomers and polymers. Plant phenols possessing a reactive group in addition to the phenolic group, such as a double bond, aldehyde, ester, alcohol or carboxylic acid, are particularly useful. Plant phenols, or a phenolic fraction, recovered from bio-oils such as pyrolysis oil are used as starting material for the monomers of the invention.