Macromonomers, poly methyl

Poly(methyl methacrylate)-g-poly(dimethylsiloxane) copolymers have been prepared by free radical copolymerizations of acrylate-functional siloxane macromonomers (29) with methyl methacrylate. Siloxane macromonomers (29) of between 1,000 and 20,000 molecular weight were utilized to give a range of copolymers with between 4 and 17 wt% silicone115. 

The mechanism of polystyrene and poly(methyl methacrylate) particle formation in the presence of PEO-MA macromonomer in the presence of conventional stabilizer (PVPo) and the graft copolymers (PSt-gra/f-PEO), respectively, was discussed [77]. At the beginning of dispersion polymerization (in methanol) of MMA (0-250 s) using PVPo, very small particles were formed (12-35 nm in diameter). The population of bigger particles was roughly stabilized at ca. 345 nm in diameter. In the dispersion polymerization of styrene, small particles... 

Pentadienyl-terminated poly(methyl methacrylate) (PMMA) as well as PSt, 12, have been prepared by radical polymerization via addition-fragmentation chain transfer mechanism, and radically copolymerized with St and MMA, respectively, to give PSt-g-PMMA and PMMA-g-PSt [17, 18]. Metal-free anionic polymerization of tert-butyl acrylate (TBA) initiated with a carbanion from diethyl 2-vinyloxyethylmalonate produced vinyl ether-functionalized PTBA macromonomer, 13 [19]. 

The reaction was shown to proceed nearly quantitatively, and the poly(methyl metha-crylate)macromonomers were copolymerized with various vinylic monomers to yield graft copolymers. 

Sharkey20 found that living poly(methyl methacrylate) reacts efficiently and without side reaction with p-vinylbenzyl iodide (or bromide) at low temperature yielding poly(methyl methacrylate) macromonomers bearing at the chain end a styryl group (poly(methyl methacrylate)macromonomer). 

Polyamide copolymers containing a macromolecular graft substituent were prepared by condensing 4-amino-benzoic acid or a mixture of 1,4-phenylene diamine and adipic acid with 33%, 66%, and 90% 5-(poly(n-butylacrylate)cysteine macromonomer. A second macromolecular monomer, 5-(poly(methyl methacrylate)-cysteine, was also prepared and free radically copolymerized with perfluoromethyl methacrylate. 

Poly(HEMA-co-MMA-g-PMMA) graft copolymer was also prepared with a commercially available poly(methyl methacrylate) (PMMA) macromonomer, HEMA, and MMA, and used as an efficient dispersant for the dispersion polymerization of styrene in ethanol [152]. 

Polymerization of the alkoxyallene with macromonomers having a poly (ethyleneglycol) group by [(7r-allyl)Ni(OCOCF3)]2/PPh3 produces a graft copolymer with narrow molecular weight distribution [129]. The products serve as polymeric surfactants in the polymer blend system of polystyrene and poly(methyl methacrylate). 

DeSimone, J. M., A. M. Hellstern, E. J. Siochi, S. D. Smith, T. C. Ward, P. M. Gallagher, V. J. Krukonis, and J. E. McGrath. 1990. Homogeneous and multiphase poly(methyl methacrylate) graft copolymers via the macromonomer method. Makro-mol. Chem., Macromol. Symp. 32 21. 

Another useful class of dispersants/emulsifiers are the graft copolymers consisting of one B chain and several A chains grafted on to the backbone. These graft copolymers are sometimes referred to as comb polymers. Examples of suitable B chains are poly(methyl methacrylate) (PMMA) or polystyrene, with A chains of PEO or PVP. The copolymer is usually prepared by grafting a macromonomer such as methoxy poly(ethylene oxide) methacrylate with poly(methyl methacrylate). 

Poly(methyl methacrylate) (PMMA) macromonomers have been prepared using thioglycolic acid as a chain-transfer agent, followed by reaction with glycidyl methacrylate (82) (eq. 21). 

Shinoda, H., and Matyjaszewski, K. (2001). Improving the structural control of graft copol5mers. Copolymerization of poly(dimethylsiloxane) macromonomer with methyl methacrylate using RAFT polymerization. Macromolecular Rapid Communications, 22(14) 1176-1181. 

Polymerization of amphiphilic macromonomer or copolymerization of hydrophobic or nonpolar monomer with hydrophilic or polar macromonomer leads to the formation of surface active polymers or grafted copolymers. Macromonomers are macromolecules with a polymerizable group (see some examples, PSt denotes polystyrene and PMMA poly (methyl methacrylate)) ... 

Star polymers exhibiting three different branches (PS, PDMS, and poly( er -butyl methacrylate) were prepared in a similar way, the first being the preparation of PDMS macromonomers containing a terminal nonpolymeriz-able DPE entity. Thus, a living PS is reacted with the PDMS macromonomers to create active sites on DPE. These sites served subsequently as initiators for the anionic polymerization of tert- mXy methacrylate [89]. Stadler and coworkers have used that reaction to generate polystyrene-arm-polybutadiene-arm-poly(methyl methacrylate) [90]. 

PIB-toughened poly(methyl methacrylate) (PMMA) networks have been reported in which the PIB domains are covalently bound to a PMMA matrix [26]. The synthesis involved a macromonomer approach where a combination of radical and cationic polymerization techniques were used. Methacrylate tri-telechelic PIBs were prepared by living cationic polymerization followed by end functionalization and used in free-radical solution copol)mierization with various amounts of MMA. Scheme 14 represents the general reaction pathways for the synthesis of network. 

Sakamoto et al. (2) prepared macromonomers consisting of poly (butyl acrylate-/7-methyl methacrylate), which were used as paint additives to enhance adhesiveness and storage stability properties. 

Thus, Yamashita succeeded in synthesizing co-methacryloyl and co-styryl-poly-dimethylsiloxane macromonomers which have subsequently been copolymerized with styrene and methyl methacrylate. 

To overcome the difficulties of ESI-MS, Simonsick and Prokai added sodium cations to the mobile phase to facilitate ionization [165,166]. To simplify the resulting ESI spectra, the number of components entering the ion source was reduced. Combining SEC with electrospray detection, the elution curves of polyethylene oxides) were calibrated. The chemical composition distribution of acrylic macromonomers was profiled across the molar mass distribution. The analysis of poly(ethylene oxides) by SEC-ESI-MS with respect to chemical composition and oligomer distribution was discussed by Simonsick [167]. In a similar approach aliphatic polyesters [168], phenolic resins [169], methyl methacrylate macromonomers [169] and polysulfides have been analyzed [170]. The detectable mass range for different species, however, was well below 5000 g/mol, indicating that the technique is not really suited for polymer analysis. 

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