Macromonomers methacrylate terminated

The GPC traces that were taken during the course of a copolymerization reaction of vinyl chloride and an 11,000 MW polystyrene methacrylate-terminated macromonomer are shown in Figure... 

Muller et al. [53] prepared similar PMMA-g-PMMA by radical copolymerization of MMA with methacrylate-terminated PMMA macromonomer, 29, and characterized the samples by SEC-multiangle laser fight scattering (MALLS). The power law exponent, a, in the equation, 1/2°cMa, was found to be 0.36. In remarkable contrast to the result of Ward et al. [51], the shrinking factor decreased with increase of MW. This may imply that the difference in graft copolymerization method, anionic or radical, results in the graft copolymers with very different branch distribution. 

PMMA macromonomers have been prepared by several methods. The most common involves the use of thioglycolic acid, as a chain transfer agent for the preparation of polymers with carboxyl end groups, followed by the reaction with glycidyl methacrylate (GMA) to introduce a methacrylate terminal group [8] (Scheme 42). 

Apart from the nse of a polymerizable alkoxysilane, silica/polystyrene composite particles with a raspberry-like morphology have been elaborated in the presence of a methyl methacrylate-terminated polyethylene glycol macromonomer. This macromonomer is mainly hydrophilic due to the presence of ethylene oxide repeat units (n 23), which are able to form hydrogen bonds with the silanol groups of silica and adsorb on its snrface. In addition, this molecnle contains a methacrylate functionality able to copoljmerize with styrene thus... 

Ueki, S., Furuhashi, H., Murakami, N. et al. (1995) Synthesis of propylene macromonomer with terminal methacryl group by vanadium-based catalyst. Science and Technology in Catalysis, 92,359-362. 

Induced deactivation of the living ionic sites is one major route to introduce the polymerizable unsaturation at chain ends. Care has to be taken, however, that no side reaction takes place simultaneously and that the active site is unable to react with the unsaturation. Typical examples include the synthesis of macromonomers—with terminal styryl or with methacrylic ester functions— upon deactivation of living anionic polymers by means of p-chloromethylstyrene or methacryloyl chloride (Scheme... 

MethacrylatE-terminated poly(L-lacUc acid) macromonomer, Mn=2800 Methacrylate-terminated poly(D,L-lactlc acid) macromonomer, M,=3350 2-Hydroxyethyl methacrylate 2-Acetoxyethyl methacrylate... 

Methacrylate-terminated poly(L-lactic acid) macromonomer, Mn=4500 Acrylate-terminated poly(L-lactic acid) macromonomer, M =26W 82-Hydroxyethyl acrylate DPE dipheiryl ether Determined by Jaacks method... 

Comb-shaped polymers are derived from polymerizing or copolymerizing macromonomers. Macromonomers can be synthesized by a variety of synthetic techniques. Asami and co-workers prepared a methacrylate-terminated polystyrene by anionic polymerization. The macromonomer was then polymerized using GTP [41] to yield an oligomer with a polystyrene backbone and PMMA grafts. McGrath and co-workers prepared a poly(dimethyl siloxane) macromonomer end-capped with a methacrylate group. This macromonomer was polymerized by GTP to yield a comb-shaped polymer with PDMS branches [19]. 

A comparison of a methacrylate terminated polyphenylene ether telechelic macromonomer versus an isophthalate modified unsaturated polyester in vinyl toluene resins reveal significant performance enhancements in a wide range of properties. 

Chain transfer to methacrylate and similar maeromonomers has been discussed in Section 6.2.3.4. The first papers on the use of this process to achieve some of the characteristics of living polymerization appeared in 1995.380 The structure of macromonomer RAFT agents (163) is shown in Figure 9.3. An idealized reaction scheme for the case of a MMA terminated macromonomer is shown in Scheme 9.36. 

Surprisingly, after this very first example, there was a 20 year delay in the literature in the appearance of the second report on siloxane macromonomers. However, during this period there have been numerous studies and developments in the vinyl and diene based macromonomers91 -94). The recent approach to the synthesis of siloxane macromonomers involves the lithiumtrimethylsilanolate initiated anionic polymerization of hexamethyltrisiloxane in THF 95,123). The living chain ends were then terminated by using styrene or methacrylate functional chlorosilanes as shown in Reaction Scheme X. 

Yamashita and co-workers have also determined the reactivity ratios of styryl terminated PDMS macromonomers (M,) with styrene (M2) and methyl methacrylate (M2)123>. They have determined (r2) and (r2) as 1.1 and 0.60 respectively. These values... 

MA and St denotes methacrylate and styrene terminated PDMS Macromonomers respectively ... 

Terminal-functionalized polymers such as macromonomers and telechelics are very important as prepolymer for construction of functional materials. Single-step functionalization of polymer terminal was achieved via lipase catalysis. Alcohols could initiate the ring-opening polymerizahon of lactones by lipase catalyst. The lipase CA-catalyzed polymerizahon of DDL in the presence of 2-hydroxyethyl methacrylate gave the methacryl-type polyester macromonomer, in which 2-hydroxyethyl methacrylate acted as initiator to introduce the methacryloyl group quanhtatively at the polymer terminal ( inihator method ).This methodology was expanded to the synthesis of oo-alkenyl- and alkynyl-type macromonomers by using 5-hexen-l-ol and 5-hexyn-l-ol as initiator, respechvely. 

A methacryl-type polyester macromonomer was synthesized by lipase PF-catalyzed polymerizahon of DDL using vinyl methacrylate as terminator ( terminator method ), in which the vinyl ester terminator was present from the beginning of the reachon (Scheme 17). In using divinyl sebacate as terminator, the telechelic polyester having a carboxylic acid group at both ends was obtained. Various non-protected thiol compounds were used as inihator or terminator for the thiol end-funchonalizahon of poly(8-CL). ... 

In our own research, the functional termination of the living siloxanolate with a chlorosilane functional methacrylate leading to siloxane macromonomers with number average molecular weights from 1000 to 20,000 g/mole has been emphasized. Methacrylic and styrenic monomers were then copolymerized with these macromonomers to produce graft copolymers where the styrenic or acrylic monomers comprise the backbone, and the siloxane chains are pendant as grafts as depicted in Scheme 1. Copolymers were prepared with siloxane contents from 5 to 50 weight percent. 

A second test was done by using butyl acrylate as the comonomer as shown in Figure 11. The reactivity ratios in this case are such that the methacrylate functionality would react slower with acrylates than with vinyl chloride. As predicted the butyl acrylate is at 62% conversion before the MACROMER peak is significantly diminished. These data add validity to the hypothesis that the placement of side chains in the backbone is dependent on the terminal group of the macromonomer and the relative reactivity of its comonomer. 

Kaneko et al. have reported the preparation of EPR macromonomers, which is useful to synthesize PMMA-g-EPR graft copolymers [106]. Graft copolymers possessing a poly(methacrylate) backbone and EPR branches were successfully synthesized by the copolymerization of EPR macromonomers with MMA. Methacryloyl terminated EPR, which were EPR macromonomers, were prepared by the sequential end functionalization of EPRs with vinylidene end group via hydroalumination, oxidation, and esterification (Fig. 20). The ATRP method can be used for the copolymeriza-... 

The preparation of PnBA-g-PE and PtBA-g-PE graft copolymers was reported using Fe-mediated olefin polymerization, chain shuttling with Zn and ATRP techniques [108]. Terminally hydroxyl PE was synthesized from Zn-terminated PE by oxidation and hydrolysis, as referred to above. It was converted to methacrylated PE, as PE macromonomer, using methacryloyl chloride. The resulting PE macromonomer was used for the copolymerization of nBA or tBA by ATRP using CuBr/tris((N,N-dimclhylamino)clhyl)aminc. The obtained graft copolymers were characterized by GPC, DSC, and JH NMR. 

A similar procedure was also used for the synthesis of methacrylate functional poly(a-MeS) [80]. Thus, 31 was used in conjunction with SnBr4 in CH2C12 at -78 °C, to obtain the macromonomer with Mns substantially (-50%) higher than the theoretical value. This was probably due to the formation of terminated low MW oligomers with indanyl end group structure. The eliminated proton was as-... 

Well-defined macromonomers of poly(BVE), poly(IBVE), and poly(EVE) with co-methacrylate end group [91] were prepared by living cationic polymerization of the corresponding monomers initiated by trifluoromethanesulfonic add in CH2C12 at -30 °C in the presence of thiolane as a Lewis base. After complete conversion, the polymers were quenched with 37 in the presence of 2,6-lu-tidine or with 41 to produce macromonomers with Mn up to 10,000 g mol-1, with narrow MWD, bearing one polymerizable methacrylate function per molecule. The same polymers were also quenched with 38 in the presence of 2,6-lutidine to give poly(vinyl ether)s with an allylic terminal group. 

End-functionalized polyethylene (PE) [8, 9], polypropylene (PP) [10], and polyisobutylene (PIB) [11] have been transformed to their corresponding macromonomers carrying (meth)acrylate, oxazoline, and methacrylate end groups, 1, 2, and 3, respectively. Polybutadienyl lithium was terminated with chlo-rodimethylsilane, followed by hydrogenation to saturated polyolefin (PHBd) [12]. Hydrosilylation of the end silane with allyl glycidyl ether afforded an epox-... 

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]. 

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