摘要:
The novel polyfunctional peroxides are compounds represented by the following general formula (1):R.sup.1 --CX.sub.3 (1)wherein R.sup.1 represents a linear alkyl group having 1 to 3 carbon atoms; and X represents a group: ##STR1## (wherein R.sup.2 represents a linear or branched alkyl group having 1 to 5 carbon atoms).Such polyfunctional peroxides include 1,1,1-tris(t-butylperoxycarbonyloxymethyl)propane and the like. The polymerization initiators for vinyl monomers comprise such polyfunctional peroxides. In the process for polymerizing vinyl monomers, a vinyl monomer is polymerized employing such polyfunctional peroxide at 60 to 160.degree. C.
摘要:
A process for the preparation of (co)polymers employing a peroxide composition comprising at least one organic peroxide wherein at least 20% of the total active oxygen content of said organic peroxide is attributable to one or more cyclic ketone peroxides represented by the following formulas I-III: ##STR1## These cyclic ketone peroxides are highly efficient as polymerization initiators. Also new cyclic ketone peroxides and compositions comprising such compounds are provided,
摘要:
Poly(monoperoxycarbonates) of the structure: ##STR1## where R, R.sup.1 and n are defined in the summary of the invention such as 1,1,1-tris(t-butylperoxycarbonyloxymethyl)ethane, intermediates for their preparation as well as processes for their preparation and use are disclosed. The monoperoxycarbonate compounds are useful in initiating the polymerization of ethylenically unsaturated monomers, particularly styrene, curing of unsaturated polyester resins, and in modifying the molecular weight of polymers such as by crosslinking or controlled chain degradation.
摘要:
A method for producing a spherical crosslinked copolymer, which comprises polymerizing a monofunctional addition-polymerizable monomer and at least 0.5% by weight of a polyfunctional addition-polymerizable monomer on the basis of the total weight of monomers by suspension polymerization in an aqueous medium in the presence of a radical polymerization initiator of the following formula (b) which has a decomposition temperature for a half-life period of 10 hours within a range of from 60.degree. to 120.degree. C. and which is capable of forming at least four radical initiating points per molecule by the decomposition:(R.sub.4 --O--O.paren close-st..sub.m R.sub.5 (b)wherein R.sub.4 is a linear or branched C.sub.1-10 alkyl group, R.sub.5 is a m-valent C.sub.4-25 hydrocarbon group, and m is an integer of at least 2, wherein the plurality of R.sub.4 per molecule may be the same or different.
摘要:
A process for producing a monovinylidene aromatic polymer having molecular weight (Mw) greater than 275,000 which comprises polymerizing a monomer mixture comprising a monovinylidene aromatic monomer in the presence of:A) from 10 to 2000 ppm by weight of at least one free radical generating, branching polymerization initiator; andB) from 10 to 2000 ppm of one or more organic gel reduction agent selected from the group consisting of:1) mercaptans, terpenes, halocarbons and halohydrocarbons, such agent having up to 20 carbons,2) distillate recovered from the reaction devolatilization process (recycle), and3) mixtures of 1) and 2).
摘要:
A novel and safe ethylenically unsaturated peroxyester composition derived from an ethylenically unsaturated dicarboxylic acid is provided, as well as processes for making and using the composition. The peroxyester composition comprises about 0.04 to about 0.70 mole fraction of a first component compound having a formula I: ##STR1## about 0.32 to about 0.50 mole fraction of a second component compound having a formula II: ##STR2## about 0.04 to about 0.70 mole fraction of a third component compound having a formula III: ##STR3## wherein Q is an unsaturated ethylene divalent radical and R.sup.1 and R.sup.2 are organic substituents. Polymeric-peroxides are prepared via polymerizing the peroxyester compositions. The peroxyester compositions are also used for curing unsaturated polyester resins and for initiating polymerization of ethylenically unsaturated monomers.
摘要:
Suspension polymers ofa) from 80 to 100% by weight of methyl methacrylate andb) from 0 to 20% by weight of further monomers capable of undergoing free radical polymerization,are obtainable by polymerization at a temperature of from 100.degree. to 140.degree. C. which is virtually constant over the major part of the polymerization time by means of an initiator system consisting of two or more peroxide initiators I having different decomposition temperatures T at which in each case half of the initiator has decomposed after 1 hour, whereinthe initiator I.sub.min having the lowest decomposition temperature has a decomposition temperature T.sub.min of from 60.degree. to 100.degree. C.,the initiator I.sub.max having the highest decomposition temperature has a decomposition temperature T.sub.max of from 100.degree. to 140.degree. C., the difference between T.sub.max and T.sub.min is greater than 10.degree. C. and I.sub.max is a perketal of the general formula (1) ##STR1## where R.sup.1 and R.sup.2 are identical or different alkyl radicals of 1 to 5 carbon atoms and R.sup.1 and R.sup.2 may be bonded to form a 5-membered or 6-membered ring and R.sup.3 is tert-butyl or tert-amyl, andfurther initiators I.sub.n which, if desired, may be concomitantly used have decomposition temperatures T.sub.n of from T.sub.min to T.sub.max.
摘要:
This disclosure relates to storageable and/or transportable compositions containing a peroxydicarbonate to which an organic hydroperoxide, e.g. t-butyl hydroperoxide, has been added. The hydroperoxide serves to retard peroxydicarbonate decomposition. The compositions may be in the form of physical mixtures, aqueous dispersions or solutions in organic solvents.
摘要:
A diacyl peroxide composition comprising 10 to 60 parts by weight of peroxide which comprises dibenzoyl peroxide, either di-m-toluoyl peroxide, or di-o-toluoyl peroxide or m-toluoyl o-toluoyl peroxide and either benzoyl m-toluoyl peroxide or benzoyl o-toluoyl peroxide and 90 to 40 parts by weight of a solvent which dissolves the diacyl peroxides does not cause the deposition of the solid matters when kept below 5.degree. C., the phase separation nor the storage degradation for a long term and can be stored for a long time.The composition usually has peroxide components which are suitable for use in place of benzoyl peroxide and excellent in the handling and the workability.