Process for the preparation of N-substituted maleimides
申请人:Tosoh Corporation
公开号:EP0393713A1
公开(公告)日:1990-10-24
N-substituted maleimide represented by formula (2):
is produced from N-substituted maleamic acid monoester represented by formula (1):
in the presence of an acid catalyst by elimination of an alcohol from the monoester. The above N-substituted maleamic acid monoester represented by formula (1) is produced by esterification of N-substituted maleamic acid represented by formula (3):
with an alcohol R² -OH in the presence of an acid catalyst.
Method for the production of homo-, co- and block copolymers
申请人:Ingrisch Stefan
公开号:US20050234191A1
公开(公告)日:2005-10-20
A process is described for producing homo-, co- and block copolymers by controlled radical polymerization in aqueous solution, wherein a monomer component (A) consisting of at least one radically polymerizable monomer, an initiator component (B) consisting of at least one radical initiator, a polysaccharide component (C) consisting of at least one cyclic polysaccharide (derivative) and a regulator component (D) consisting of at least one compound of the general formula (Ia) or/and (Ib) are reacted in the presence of water,
in which R
1
to R
6
can each independently denote hydrogen, an optionally substituted C
1
-C
20
alkyl residue, C
3
-C
8
cycloalkyl residue, C
7
-C
34
aralkyl residue or optionally an aromatic C
6
-C
14
hydrocarbon residue and R
2
and R
5
can additionally denote polymer residues having an average molecular mass (number average) of 100 to 50,000 Daltons, and at least two but at most four of the residues R
1
to R
6
represent an aromatic hydrocarbon residue. In this manner it is possible to produce polymers with a very narrow molecular weight distribution. Moreover, due to the much lower amounts of initiator and regulator compared to the prior art, the polymers contain only very small amounts of regulator and initiator decomposition products.