Methyl methacrylate-ethylene glycol dimethacrylate copolymerization

The first case is the copolymerization of monomer A with diene BB where all the double bonds (i.e., the A double bond and both B double bonds) have the same reactivity. Methyl methacrylate-ethylene glycol dimethacrylate (EGDM), vinyl acetate-divinyl adipate (DVA), and styrene-p- or m-divinylbenzene (DVB) are examples of this type of copolymerization system [Landin and Macosko, 1988 Li et al., 1989 Storey, 1965 Ulbrich et al., 1977]. Since r = Yi, Fi = f and the extent of reaction p of A double bonds equals that of B double bonds. There are p[A] reacted A double bonds, p[B] reacted B double bonds, and p2[BB] reacted BB monomer units. [A] and [B] are the concentrations of A and B double bonds,... 

The previous concepts may be illustrated with the experimental determination of the evolution of reaction rate, measured by DSC at T = 60°C, for the copolymerization of methyl methacrylate (MMA) with variable amounts of ethylene glycol dimethacrylate (EGDMA), a vinyl-divinyl system (Sun et al., 1997). The reaction was initiated with 2,5-dimethyl-2,5-bis(2-ethylhexanoyl)peroxy hexane. 

Fig. 24 Experimental results for the weight-average molecular weight development during the emulsion crosslinking copolymerization of styrene (St)/divinylbenzene (DVB) and methyl methacrylate (MMA)/ethylene glycol dimethacrylate (EGDMA). Data from [323]...

Predict the extent of reaction at which gelation would occur in the following two vinyl-divinyl systems, both containing 1 mol% of the divinyl component (a) styrene-ethylene glycol dimethacrylate and (b) methyl methacrylate-divinyl benzene. Assume that the reaction conditions for the two systems are such as to yield the same DP. of 1000 for the uncrosslinked polymer. Take the r and T2 values from Table 7.1 for the analogous vinyl-vinyl copolymerizations. [Ans. (a) Pc = 0.015 (b) p, = 0.012.]... 

Problem 7.17 Bulk polymerization of methyl methacrylate (MMA) at 60°C with 0.9 g/L of benzoyl peroxide yielded a polymer with a weight average degree of polymerization of 8600 at low conversions. Predict the conversions of MMA at which gelation would be observed if it is copolymerized with 0.05 mol% of ethylene glycol dimethacrylate (EGDMA) at the same temperature and initiator concentration as in the homopolymerization case. 

An analog of monomer 288 has been prepared replacing the phthalazine by a 2,5-diphenylpyrimidine and the corresponding monomer 290 was copolymerized with methyl methacrylate or ethylene glycol dimethacrylate to lead to the copolymers 291a and 291b respectively (Scheme 116) [177]. Unfortunately, the enantioselectivities were aroimd 15-45% lower than those observed with the phthalazine-derived supported dihydroquinidine 289. 

Much of the work reported in the academic literature is based upon microgels prepared from poly(NIPAM), but there are, however, a number of microgels that have been prepared from other monomers. These include methyl methacrylate with other copolymers such as ethylene glycol dimethacrylate (17,18), methyl methacrylate with p-divinylbenzene (19), and methyl methacrylate with methacrylic acid (20). Other microgel particles have been prepared from poly(allylamine hydrochloride) (21), vinylpyrrolidinone and acrylic acid (22), acrylamide and acrylamide with methacrylamidopropyltrimethylammonium chloride (23), and acrylamide copolymerized with 2-acrylamido-2-methylpropanesulfonic acid (24). 

For example, contact lenses are prepared by the copolymerization of 2,2,3,3,4,4,4-heptafluorobutyl methacrylate, tri-n-octyl-3-vin-ylbenzyl phosphonium chloride, methyl-di(trimetiiylsiloxy)silyl-propyl methacrylate, and ethylene glycol dimethacrylate. Isopropyl percarbonate is used as radical initiator. The resulting resin rod was cut and polished to obtain the contact lenses (10). 

Bouhier, M.-H., Cormack, P, Graham, S., Sherrington, D.C. Synthesis of densely branched poly(methyl methacrylate)s via ATR copolymerization of methyl methacrylate and ethylene glycol dimethacrylate. J. Polym. Sd. Ptut A Polym. Chem. 45(12), 2375-2386 (2007)... 

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