141-20-8Relevant articles and documents
PRECIPITATION POLYMERIZATION IN THE PRESENCE OF GLYCERIN MONOSTEARATE
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, (2011/06/28)
A process for preparing a copolymer composition A) by free-radical copolymerization of a monomer composition comprising: a) acrylic acid, b) optionally at least one compound, different from a), having a free-radically polymerizable, α,β-ethylenically unsaturated double bond and at least one anionogenic and/or anionic group per molecule, c) at least one free-radically polymerizable crosslinking compound which comprises at least two α,β-ethylenically unsaturated double bonds per molecule. The process is performed by precipitation polymerization in the presence of an auxiliary composition H) comprising H1) glycerol monostearate, and H2) at least one compound with an HLB value in the range from 4 to 10, selected from water-insoluble natural waxes, nonionic emulsifiers and mixtures thereof.
Combinatorial synthesis of PEG oligomer libraries
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Page/Page column 11, (2010/02/15)
A simple chain-extending approach was established for the scale-up of the monoprotected monodisperse PEG diol materials. Reactions of THP-(OCH2CH2)n—OMs (n=4, 8, 12) with a large excess of commercially available H—(OCH2CH2)n—OH (n=1-4) under basic conditions led to THP-(OCH2CH2)n—OH (n=5-15). Similarly, Me-(OCH2CH2)n—OH (n=4-11, 13) were prepared from Me-(OCH2CH2)n—OMs (n=3, 7, 11). For the chain elongation steps, 40-80% yields were achieved through extraction purification. PEG oligomer libraries I and II were generated in 50-95% overall yields by alkylation or acylation of THP-(OCH2CH2)n—OH (n=1-15) followed by deprotection. Alkylation of Me-(OCH2CH2)n—OH (n=1-11, 13) with X—(CH2)m—CO2R (X=Br or OMs) and subsequent hydrolysis led to PEG oligomer library III in 30-60% overall yields. Combinatorial purification techniques were adapted to the larger-scale library synthesis. A total of 498 compounds, each with a weight of 2-5 g and a minimum purity of 90%, were synthesized.