摘要:
Novel peroxydicarbonates are provided in which the alkyl carbonate moiety is 2-alkyl-2-phenyl substituted. The compounds are useful as polymerization initiators of ethylenically unsaturated monomers, such a vinyl chloride, and as catalysts of unsaturated polyester resins. The subject peroxydicarbonates are characterized in that they are solid at room temperature, have ambient temperature stability in spite of a low 10 hour half-life temperature, and can normally be transported and stored without refrigeration.
摘要:
Novel mono and di peroxyesters characterized by chloro-substitution of a tertiary carbon atom at the alpha position relative to the carbonyl group(s), the monoperoxyesters having no less than 9 carbon atoms and the diperoxyesters having no less than 16 carbon atoms, are utilized as polymerization initiators. Typical is the polymerization of styrene and the copolymerization of vinyl chloride and vinyl acetate.
摘要:
Novel mono and di peroxyesters characterized by chloro-substitution of a tertiary carbon atom at the alpha position relative to the carbonyl group(s), the monoperoxyesters having no less than 9 carbon atoms and the diperoxyesters having no less than 16 carbon atoms, are utilized as polymerization initiators. Typical is the polymerization of styrene and the copolymerization of vinyl chloride and vinyl acetate.
摘要:
Novel peroxydicarbonates are provided in which the alkyl carbonate moiety is 2-alkyl-2-phenyl substituted. The compounds are useful as polymerization initiators of ethylenically unsaturated monomers, such as vinyl chloride, and as catalysts of unsaturated polyester resins. The subject peroxydicarbonates are characterized in that they are solid at room temperature, have ambient temperature stability in spite of a low 10 hour half-life temperature, and can normally be transported and stored without refrigeration.
摘要:
Dialkyl diacyl peroxides in which the alpha carbon atom of one of the alkyl groups is secondary and substituted by chloro and alkyl. The compounds are useful as polymerization initiators of ethylenically unsaturated monomers such as vinyl chloride.
摘要:
Dialkyl diacyl peroxides in which the alpha carbon atom of one of the alkyl groups is secondary and substituted by chloro and alkyl. The compounds are useful as polymerization initiators of ethylenically unsaturated monomers such as vinyl chloride.
摘要:
Novel processes and compositions are provided for the preparation of foamed, crosslinked polyethylene utilizing cyclic peroxyketal crosslinking/blowing agents. The novel compositions include esters of thiodipropionic acid as activators.
摘要:
Unsaturated polyester resin foams or cellular structures of varying low densities are prepared quickly at ambient temperatures from an admixture which comprises a liquid unsaturated curable polyester resin, an organic isocyanate compound, a suitable surfactant, an accelerator and a particular combination of peroxide curing agents, which also serves to initiate the release of gases that permit expansion of the resin in a controlled manner to obtain a foamed structure.
摘要:
A silicon peroxide selected from the formulas:(R').sub.4-n --Si--(OOR).sub.n (a) ##STR1## wherein n is an integer of 1-3; R is a t-octyl group in which a tertiary carbon atom is directly bonded to the peroxy group; and R' is selected from alkyl, phenyl, and alkenyl (provided n is not more than 2), and a carbon chain which forms a saturated heterocyclic ring with the silicon atom, each R' group having up to about 10 carbon atoms. Typical is trimethyl (2,4,4-trimethyl-2-pentylperoxy) silane. These molecules are useful as catalysts for curing polyester resins and are particularly advantageous as crosslinking agents for high density polyethylene in that crosslinking is effected at lower temperatures than required by the prior art.
摘要:
Gem-diperoxyesters of the formula: ##STR1## where R is selected from methyl and ethyl; R.sub.1 is ethyl when R is ethyl; R.sub.1 is hydroxyalkyl of 1 to 7 carbon atoms when R is methyl; and each R.sub.2 is ##STR2## where each of R.sub.3, R.sub.4, and R.sub.5 is selected from hydrogen and alkyl, provided not more than one of R.sub.3, R.sub.4, and R.sub.5 is hydrogen, R.sub.3, R.sub.4, and R.sub.5 collectively containing from 2 to 12 carbon atoms.The compounds are particularly efficient at varying temperatures from ambient to 60.degree. C. for the initiation of the polymerization of vinyl chloride. They also have high efficiency in the curing of polyester resins and in the polymerization of other monomers and comonomers having ethylenic unsaturation.