摘要:
There is a need for odorless rubbery polymers that offer high heat resistance, ultraviolet light resistance and low fogging characteristics. For instance, rubbery polymers of this type are needed by the automotive and construction industries. The deodorized rubbery polymers of this invention are of particular value because they can be blended with polyvinyl chloride to make leathery compositions having good heat and ultraviolet light resistance. The present invention more specifically discloses a process for preparing a deodorized rubbery polymer which comprises the steps of (1) polymerizing in a first stage (a) butyl acrylate, (b) at least one member selected from the group consisting of methyl methacrylate, ethyl methacrylate, methyl acrylate and ethyl acrylate, (c) acrylonitrile and (d) a crosslinking agent under emulsion polymerization conditions to produce a seed polymer containing latex, wherein said polymerization is initiated with a redox initiator system, wherein the redox initiator system is comprised of a free radical generator and a reducing agent; (2) adding (a) styrene, (b) additional acrylonitrile, (c) additional crosslinking agent and (d) additional free radical generator to the seed polymer containing latex under emulsion polymerization conditions which result in the formation of an emulsion containing the rubbery polymer; and (3) recovering the rubbery polymer from the emulsion containing the rubbery polymer.
摘要:
The present invention is directed to a process of atom (or group) transfer radical polymerization for the synthesis of novel homopolymer or a block or graft copolymer, optionally containing at least one polar group, with well defined molecular architecture and narrow polydispersity index, in the presence of an initiating system comprising (i) an initiator having a radically transferrable atom or group, (ii) a transition metal compound, and (iii) a ligand; the present invention is also directed to the synthesis of a macromolecule having at least two halogen groups which can be used as a macroinitiator component (i) to subsequently form a block or graft copolymer by an atom or group transfer radical polymerization process; the present invention is also directed to a process of atom or group transfer radical polymerization for the synthesis of a branched or hyperbranched polymer; in addition, the present invention is directed to a process of atom or group transfer radical polymerization for the synthesis of a macroinitiator which can subsequently be used to produce a block or graft copolymer.
摘要:
A process for the preparation of branched thermoplastic resins comprising: heating a mixture of an unsaturated resin, a free radical initiator, and a stable free radical agent; adding to the heated mixture at least on polymerizable monomer; and cooling the mixture, wherein the resulting product is a branched thermoplastic resin with arms or branches comprised of polymerized monomer with substantially uniform length and narrow polydispersity.
摘要:
Rubber-modified molding materials having improved impact strength in combination with good flow behavior can be prepared by special graft polymerization of monomers forming hard graft shells, such as styrene and acrylonitrile, in the presence of an elastomeric acrylate macromonomer copolymer dissolved or swollen in these monomers, the graft polymerization being carried out, to a conversion of more than 15% by weight of the monomers, by thermal or free radical mass or solution polymerization.
摘要:
A methyl methacrylic resin composition comprising:(A) 30 to 60% by weight of an unsaturated monomer mixture comprising an unsaturated monomer having at least two double bonds which can effect radical polymerization,(B) 40 to 70% by weight of resin particles made of a polymer of a methyl methacrylic unsaturated monomer comprising (i) 20 to 100 parts by weight of partially cross-linked resin particles and (ii) 0 to 80 parts by weight of uncross-linked resin particles and(C) 0.1 to 5% by weight of a radical polymerization initiator, is provided. The resin composition has an excellent handling property, generates little odor, and can be easily molded. The methyl methacrylic resin composition gives a molded article which has a high transparency, a high hardness of the surface and an excellent scratch-resistance. The molded article may be preferably used as a lamp cover.
摘要:
A sprayable aqueous coating composition for motor vehicles comprising an aqueous dispersion of addition polymer microparticles having a crosslinked core and a non-crosslinked stabilising mantle containing acid groups, characterised in that the crosslinked core comprises: i) a crosslinked inner core of an addition polymer and ii) a crosslinked outer core of addition polymer which is made from at least 10% by weight of monomers having a solubility in water of less than 0.1% by weight ratio of the inner core to the outer core being in the range 10:90 to 90:10.
摘要:
This invention provides the preparation of water-dispersible polyester/acrylic hybrids via a two-stage emulsion polymerization process. For example, methacrylic acid and/or 2-hydroxyethyl methacrylate are copolymerized with styrene/acrylic monomers to yield a relatively hydrophilic and hydro-plasticized first stage. Subsequent additions of hydrophobic monomers to this first stage "seed" results in an inversion of the latex such that the more hydrophilic first stage is at the particle surface. This results not only in improved stability of the resulting latex without the use of additional surfactants, as evidenced by the production of reduced amounts of coagulum, while it also offers relatively low minimum filming temperatures due to the hydroplasticization of the shell of the particle. Furthermore, the use of the water-dispersible polyester results in extremely fine latex particle sizes which can significantly enhance coating properties such as film gloss and clarity.
摘要:
Aqueous coating compositions containing at least 2 polymer components which provide adhesion and improved durability as measured by improved gloss retention or dirt pick up resistance in dried coatings made from the coating composition are disclosed.
摘要:
A novel class of interpenetrating polymer networks which are dispersible in conventional coating solvents is disclosed. Such dispersions are useful in preparing protective and/or decorative film coatings and are particularly useful in photosensitive or imaging formulations such as photoresists, solder masks and the like. These polymer networks are comprised of at least two interpenetrating crosslinked polymers. At least one of the polymer networks is formed by polymerization in a solvent. In one embodiment of this invention, at least one polymer network is prepared from macromers to produce a polymer system having functionalized branch or graft linear segments. The solvent dispersible interpenetrating networks of this invention are particularly useful as binders in addition polymerizable photosensitive compositions containing crosslinking monomers such as solder masks. Upon exposure to actinic radiation and suitable thermal curing, solder mask coatings of such photosensitive compositions form multiple, e.g., triple, interpenetrating polymer networks having superior toughness and flexibility.
摘要:
This invention relates to stable one-part latex compositions prepared by aqueous emulsion polymerization wherein a core-shell polymer is formed, the core formed by emulsion polymerization of an ethylenically unsaturated monomer in the presence of an epoxy resin and the shell polymer formed by emulsion polymerization of a hydroxy carboxyl containing monomer composition in the presence of the core, providing that the monomers in both the core and the shell do not contain amino functional groups, and post-adding to the formed core-shell polymer an organic compound having at least one amino functional group which is available for later reaction with the epoxy resin upon drying to produce a crosslinked polymer product.