Water → Methyl Methacrylate

Participants

Reaction Steps

A solution of 1 mL (5 mmol) of 1-methoxy-1-trimethylsiloxy-2-methyl-1-propene, and 0.132 mL of tetrabutylammonium m-chlorobenzoate (0.38 M in THF), in 75 mL of THF was prepared. To this was added a mixture of 12.5 g (13.35 mL, 125 mmol) of MMA and 2.5 g (14 mL, 87.9 mmol) of n-butyl methacrylate at a rate such that the temperature remained near 30° C. When the monomer mixture had all been added, and 15 min after the temperature had returned to room temperature, a sample removed for NMR analysis showed no residual monomers. GPC analysis showed Mn 5390, Mw 5990, D=1.11 (theory Mn=5252). Then 5 g (20 mmol) of bis(trimethylsilyl) vinylphosphonate (prepared from the reaction of bromotrimethylsilane with diethyl vinylphosphonate) was added, followed by 4 additions of 200 μL TASHF2 (0.1 M in propylene carbonate). A sample was removed for analysis. NMR analysis showed residual vinylphosphonate. GPC analysis showed Mn 5840, Mw 6240, D=1.067. The polymer was precipitated with hexane to give a gummy polymer. This was redissolved in the minimum amount of THF and reprecipitated with hexane to yield 23.6 g of copolymer. NMR analysis showed 1.35 MMA units per butyl methacrylate unit (theory 1.42:1). The copolymer was dissolved in 70 mL of THF and treated with 5 mL of water and stirred 1.5 hr. After precipitation with 1:1 methanol:water, the resulting polymer (205 g) was dissolved in 50 mL of THF and treated with 5 mL of water and 0.5 g of p-toluenesulfonic acid and stirred for 2 hrs. Precipitation with aqueous methanol gave copoly(methyl methacrylate, n-butyl methacrylate) with a terminal phosphonic acid group.

Provenance & Evidence