Graft copolymerization styrene

It is possible to graft copolymerize styrene-maleic anhydride or styrene-methyl methacrylate onto polymer chains [224,225] and produce much higher concentration of maleic anhydride or methyl methacrylate. 

Miscellaneous Copolymers. VP has been employed as a termonomer with various acryUc monomer—monomer combinations, especially to afford resins usehil as hair fixatives. Because of major differences in reactivity, VP can be copolymerized with alpha-olefins, but the products are actually PVP grafted with olefin or olefin oligomers (151,152). Likewise styrene can be polymerized in the presence of PVP and the resulting dispersion is unusually stable, suggesting that this added resistance to separation is caused by some grafting of styrene onto PVP (153). The Hterature contains innumerable references to other copolymers but at present (ca 1997), those reviewed in this article are the only ones known to have commercial significance. 

Thermoplastic elastomers are often multiphase compositions in which the phases are intimately dispersed. In many cases, the phases are chemically bonded by block or graft copolymerization. In others, a fine dispersion is apparentiy sufficient. In these multiphase systems, at least one phase consists of a material that is hard at room temperature but becomes fluid upon heating. Another phase consists of a softer material that is mbberlike at RT. A simple stmcture is an A—B—A block copolymer, where A is a hard phase and B an elastomer, eg, poly(styrene- -elastomer- -styrene). 

A waterborne system for container coatings was developed based on a graft copolymerization of an advanced epoxy resin and an acryHc (52). The acryhc-vinyl monomers are grafted onto preformed epoxy resins in the presence of a free-radical initiator grafting occurs mainly at the methylene group of the aHphatic backbone on the epoxy resin. The polymeric product is a mixture of methacrylic acid—styrene copolymer, soHd epoxy resin, and graft copolymer of the unsaturated monomers onto the epoxy resin backbone. It is dispersible in water upon neutralization with an amine before cure with an amino—formaldehyde resin. 

Graft copolymerization of acrylonitrile with various vinyl comonomers such as methyl acrylate, ethyl acrylate, vinyl acetate, and styrene onto cellulose derivatives using ceric ion was studied [24]. The results showed that... 

Radio-chemical graft copolymerization with good efficiency on halogenated polyolefins has been carried out by contacting the substrate with monomer (styrene) vapor [158,159]. Interpenetrating polymer network (IPN) could be made by grafting the monomers on preirradiated substrates... 

Liquid phase graft copolymerization with chloromethylstyrene and styrene... 

Ohkoshi, M. (1991). Bonding of wood by thermoplasticizing the surfaces II. Possible crossUnking of wood by the graft-copolymerizing of styrene onto allylated surfaces. Mokuzai Gakkaishi, 37(10), 917-923. 

In situ FC tests have shown that these membranes are capable of performances at least comparable to Nafion under fully humidified, 60°C operation conditions. Lifetimes were typically short however, with the introduction of DVB as a cross-linker during the graft copolymerization with styrene, lifetimes could be improved to around 1,000 hours. This could be further improved to over 6,(300 hours using a combination of DVB and triallyl cyanuarate as cross-linkers. ... 

After 30-40 min the mixture warms up, indicating that the crosslinking graft copolymerization has begun.The sample gels and after 1 h has become almost solid, most of the styrene having polymerized. 

Grafting of styrene (ST) onto polybutadiene (PB) can occur in two ways Via a chain-transfer reaction with an allylic hydrogen of the 1,4- and the 1,2-units (Case 1) via copolymerization with C=C-double bounds of polybutadiene, in particular with the vinyl groups of the 1,2-units (Case 2) ... 

Fig. 2 A Oscillator frequency changes with graft copolymerization of styrene (ST) on the dithiocarbamated copolymer-coated quartz crystal microbalance (QCM) in methano-lic solution with UV irradiation (light intensity 5mWcm ). Concentration of ST a 0, h 0.26, c 0.5, d 0.76 mol dm . B Relationship of oscillator frequency change calculated from A with concentration of ST...

R. Qi, J. Qian, Z. Chen, X. Jin, and C. Zhou, Modification of acrylo-nitrile-butadiene-styrene terpolymer by graft copolymerization with maleic anhydride in the melt. II. Properties and phase behavior, J. Appl. Polym. Sci., 91(5) 2834-2839, March 2004. 

E.A. Abdel-Razik, Photoinduced graft copolymerization of acrylamide onto styrene-butadiene-acrylonitrile copolymer, J. Photocltem. Photobiol., A, 69(1) 121-124, October 1992. 

C. Deacon and C.A. Wilkie, Graft copolymerization of acrylic acid on to acrylonitrile-butadiene-styrene terpolymer and thermal analysis of the copolymers, Eur. Polym. J., 32(4) 451-455, April 1996. 

High impact strength thermoplastic resins can be prepared by mixing a styrene/acrylonitrile copolymer with rubber particles. In general, the styrene/acrylonitrile copolymer is prepared by the graft copolymerization of styrene and acrylonitrile in the presence of rubber itself (17). 

GRAFT COPOLYMERIZATION OF VINYL MONOMERS ONTO POLYMERS CONTAINING STYRENE... 

Chemical processes are far more varied and may involve either the formation of radicals or ions along a polymeric backbone. Both cationic processes3 as well as radical processes have been widely used for graft copolymerization of vinyl monomers onto various polymers. Radical graft copolymerization has been reported for many polymers including styrene-butadiene block copolymers, and acrylonitrile-butadiene-styrene terpolymer, ABS.3 7 9... 

In this paper graft copolymerization onto both polystyrene and styrene-butadiene block copolymer will be discussed. It will be shown that radical processes do not permit the addition of monomers onto polystyrene and that one must use anionic initiation in order... 

Chemical Initiation of Graft Copolymerization onto Styrene-Butadiene Block Copolymer... 

One may perform radical graft copolymerizations onto the butadiene region of copolymers of styrene and butadiene without any reaction occurring at the styrene portions of the copolymer. If the monomer is reactive, reaction of the monomer at an allylic site occurs while for less reactive monomers, the polymeric radical is formed and this adds to the double bond of the polymer. Proof of the site of grafting comes from information about the relative efficiency of different initiators but the most important information is obtained from infrared spectroscopy. One can observe differences in the spectra which can be related to the mode of addition. 

E, A. Abdel-Razik, Photoinduced graft copolymerization of acrylamide onto styrene-butadiene-acrylonitrile... 

The simplest procedure for grafting copolymerization, in terms of number of components in the reaction medium, is a bulk polymerization of the monomer in mixture with the molten polyamide. This has been claimed in an earlier patent (2), related to improvements in dyeability and hydrophylic properties of the resulting yam, obtained by melt spinning of the product of reaction with monomers such as 2,5-dichloro styrene, lauryl methacrylate, N-vinyl pyrrolidone, and N-vinyl carbazole. 

---