Reactivity ratios and microstructure of vinyl acetate–butyl methacrylate copolymers: NMR study

1994 ◽  
Vol 51 (4) ◽  
pp. 669-674 ◽  
Author(s):  
A. S. Brar ◽  
Shiv Charan
Keyword(s):  
Vinyl Acetate ◽  
Butyl Methacrylate ◽  
Reactivity Ratios ◽  
Nmr Study ◽  
Methacrylate Copolymers

scholarly journals Separation of Poly(styrene-block-t-butyl methacrylate) Copolymers by Various Liquid Chromatography Techniques

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Tina Šmigovec Ljubič ◽  
David Pahovnik ◽  
Majda Žigon ◽  
Ema Žagar
Keyword(s):  
Liquid Chromatography ◽  
Block Copolymers ◽  
Molar Mass ◽  
Small Difference ◽  
Reversed Phase ◽  
Butyl Methacrylate ◽  
Critical Conditions ◽  
Chromatographic Techniques ◽  
Methacrylate Copolymers ◽  
Gradient Liquid Chromatography

The separation of a mixture of three poly(styrene-block-t-butyl methacrylate) copolymers (PS-b-PtBMA), consisting of polystyrene (PS) blocks of similar length andt-butyl methacrylate (PtBMA) blocks of different lengths, was performed using various chromatographic techniques, that is, a gradient liquid chromatography on reversed-phase (C18 and C8) and normal-phase columns, a liquid chromatography under critical conditions for polystyrene as well as a fully automated two-dimensional liquid chromatography that separates block copolymers by chemical composition in the first dimension and by molar mass in the second dimension. The results show that a partial separation of the mixture of PS-b-PtBMA copolymers can be achieved only by gradient liquid chromatography on reversed-phase columns. The coelution of the two block copolymers is ascribed to a much shorter PtBMA block length, compared to the PS block, as well as a small difference in the length of the PtBMA block in two of these copolymers, which was confirmed by SEC-MALS and NMR spectroscopy.

scholarly journals Preparation and modification of itaconic anhydride-methyl methacrylate copolymers

2007 ◽  
Vol 72 (12) ◽  
pp. 1507-1514 ◽  
Author(s):  
Milos Milovanovic ◽  
Snezana Trifunovic ◽  
Lynne Katsikas ◽  
Ivanka Popovic
Keyword(s):  
Free Radical ◽  
Methyl Methacrylate ◽  
1H Nmr Spectroscopy ◽  
Copolymer Composition ◽  
Reactivity Ratios ◽  
Complete Conversion ◽  
Monomer Reactivity Ratios ◽  
Itaconic Anhydride ◽  
Methacrylate Copolymers ◽  
Butyl Amine

The free radical copolymerisation of itaconic anhydride and methyl methacrylate in solution was studied at 60 ?C. The copolymer composition was determined by 1H-NMR spectroscopy and the obtained monomer reactivity ratios were calculated, rITA = 1.35?0.11; rMMA = 0.22?0.22 (by the Fineman-Ross method) and rITA = 1.27?0.38; rMMA = 0.10?0.05 (by the Mayo-Lewis method). The synthesised copolymers were modified by reaction with di-n-butyl amine. The copolymer composition after amidation was determined by elemental analysis via the nitrogen content. Amidation of the anhydride units in the copolymers with di-n-butyl amine resulted in complete conversion to itaconamic acid.

Sign in / Sign up

Export Citation Format

Share Document