摘要:
The invention relates to a method of preparing a composite suitable as an oxidizing component in a redox aqueous emulsion polymerization initiator starting with the relatively harsh oxidation of p-diisopropylbenzene with oxygen and involving a manipulative separation procedure for obtaining the effective oxidizing component. The invention also relates to the oxidizing component, the redox polymerization initiator and to the aqueous emulsion polymerization of selected unsaturated monomers.
摘要:
There is provided a curable anaerobic pressure sensitive adhesive composition, a mixture of a curable anaerobic system and a high molecular weight polymer system. The mixture which may include a tackifier and other functional additives constitutes a pressure sensitive adhesive and exhibits elastomeric properties. There is also provided in the composition an initiator systemnecessary to permit curing of the anaerobic pressure sensitive composition upon activation by the exclusion of oxygen. One or more accelerators for cure may also be provided.In one embodiment a component of the catalyst system may be either absent and provided later or latently present in microspheres which upon rupture will enhance the curing operation.
摘要:
A process for producing an aqueous dispersion of ethylene-vinyl acetate copolymer containing no formalin by emulsion-polymerizng ethylene and vinyl acetate and optionally other copolymerizable vinyl monomers in the presence of a redox catalyst consisting of an oxidizing agent and a reducing agent, which is characterized in that a reaction product of a glyoxal compound and an alkali metal, ammonium or zinc salt of a reductive sulfur oxide is used as the reducing agent for the redox catalyst, in which process the polymerization temperature is easily controlled.
摘要:
There is provided a curable anaerobic pressure sensitive adhesive composition, a mixture of a curable anaerobic system and a high molecular weight polymer system. The mixture which may include a tackifier and other functional additives constitutes a pressure sensitive adhesive and exhibits elastomeric properties. There is also provided in the composition an initiator system necessary to permit curing of the anaerobic pressure sensitive composition upon activation by the exclusion of oxygen. One or more accelerators for cure may also be provided.In one embodiment a component of the catalyst system may be either absent and provided later or latently present in microspheres which upon rupture will enhance the curing operation.
摘要:
A process for the polymerization of vinyl or vinylidene-group-containing esters in the presence of a free radical generating compound as an initiator and a metal compound as an accelerator comprising, as an initiator, an organic peroxidic composition consisting essentially of a compound having the general formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 may be the same or different and each represents hydrogen, branched or unbranched alkyl, if desired substituted by hydroxy, alkoxy, alkoxycarbonyl or halogen, aryl, if desired substituted by alkyl, hydroxy, alkoxy or halogen, or aralkyl wherein the aryl group may be substituted by alkyl, hydroxy, alkoxy or halogen, and wherein R.sub.1 together with R.sub.2, R.sub.3 together with R.sub.4, and R.sub.1 together with R.sub.4 form a branched or unbranched alkylene group, and R.sub.1 together with R.sub.2 and R.sub.3 form a branched or unbranched alkylylidene group.
摘要:
Unsaturated polyester resin compositions contain an amine accelerator of formula ##STR1## wherein R.sup.1 and R.sup.2 are alkyl, hydroxyalkyl or carboxyalkyl groups and R.sup.3, R.sup.4 and R.sup.5 are alkyl, aralkyl, cycloalkyl, alkoxy or halogen groups.
摘要:
Vinylidene chloride polymers and copolymers are prepared by contacting vinylidene chloride monomer alone or in mixture with other ethylenically unsaturated monomers with a catalytic system consisting of an organic per-compound, an organic compound of zirconium or cobalt and an acid compound according to the definition of Bronsted and Lowry in an organic solvent medium.High yields and polymerization speeds are achieved at low polymerization temperatures (10.degree.-35.degree. C).
摘要:
New copolymers obtained by interpolymerization of alkylacrylate (25 to 85 %), methacrylic acid (15 to 75 %), trialkyloxyvinylsilane (0.1 to 2 %) and monomer acting as reticulating agent, for example: divinylbenzene, alkyl compound, etc. (0.01 to 0.5 %). The above indicated percentages are in weight of the total monomer mixture.These copolymers are used, in form of emulsions, as thickening agents for aqueous systems of polymers, for example of acrylic copolymers.
摘要:
A process for polymerizing acrylonitrile monomer or copolymerizing a mixture of acrylonitrile monomer and further ethylenically unsaturated monomers copolymerizable therewith, which comprises contacting the monomer or mixture of monomers in an aqueous medium at a temperature not exceeding 55.degree.C with a catalytic system comprising a watersoluble persulphate, a hydroxylamine mono- or disulfonate and a water-soluble salt of a variable valence metal, such as a ferrous salt.