Olefin-terminated PMMA

Olefin-terminated poly(methyl methacrylate) (PMMA) 4 can be prepared by free radical polymerization of MMA using cobalt complexes as catalytic chain transfer agents (3). 

One such reported example is the synthesis of polypropylene-6-polymethyl-methacrylate (PP-6-PMMA) copolymers utilizing metallocene catalysis and the borane chemistry. In the initial step, PP with chain-end olefinic unsaturations was prepared using metallocene catalysts such as Et(Ind)2ZrCl2/MAO. The unsaturation sites were then hydroborated by 9-borabicyclo[3.3.1]nonane (9-BBN) to produce borane-terminated PP (43) (Fig. 30), which was selectively oxidized and interconverted to a... 

Block copolymers can be produced from terminally borane-containing polyolefins. These borane-containing POs can be synthesized by the metallocene-catalyzed (co)polymerization of olefin(s) monomer with 9-BBN as a chain transfer agent or by the metallocene catalyzed copolymerization of olefins with allyl-9-BBN [55,56], as referred to above. Alternatively, borane-containing POs were prepared by hydroboration of terminally unsaturated PO, for instance, terminally vinyl PE and terminally vinylidene PP [33-35,57]. Such method could produce diblock copolymers, such as polyethylene-block-poly(methyl methacrylate) (PE-fo-PMMA), polypropylene-foZock-poly(methyl methacrylate) (PP-fc-PMMA), polypropylene-foZock-poly(butyl methacrylate) (PP-fc-PBMA), and PP-fc-PS. 

The H NMR spectrum of PMMA prepared with AIBN at 60°C showed vinylidene proton signals at 5.4 and 6.14ppm38 (Fig. 14). No inner olefin proton signal was observed. The intensity measurement indicated that 36% of the polymer molecules contained the unsaturated terminal. The thermal stability of radically prepared PMMA was discussed in relation to the... 

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