Patent ID: 6103789
Filing Date: 2000-08-15
Classification: C08F

Abstract:
Hydrosoluble acrylic copolymers, having weight average molecular weight in the range 5,000-80,000, determined as the value corresponding to the maximum of the elution peak (GPC determination), containing in the molecule the following repeating units: ##STR4## wherein: the molar ratio between the unit (I) and unit (II) in the polymer ranges from 1:1 to 50:1;in unit (I) R.sub.A, R.sub.B, R.sub.C, equal or different, are H or CH.sub.3 ; M.sup.+ is H or a cation belonging to the IA, IIA group, or ammonium;in unit (II) R.sub.I, R.sub.II, equal or different, are H or CH.sub.3 ; n is an integer from 0 to 2, A.sub.0 is --COO--(R.sub.T O).sub.m --R.sub.Z wherein R.sub.T is a saturated alkyl group having from two to four carbon atoms, m is an integer from 7 to 50, R.sub.Z is an hydrogen atom or a saturated alkyl group from 1 to 4 carbon atoms;R.sub.III is H, COOH, COO.sup.- M.sup.+ wherein M.sup.+ is as above defined or A.sub.0 as above defined;optionally containing from 0 to 20%, on the total monomer weight, of repeating units from one or more of the following monomers:(meth)acrylic ester of C.sub.1 -C.sub.20 aliphatic alcohols;polyethoxymonoallyl alkylethers of formula CH.sub.2 .dbd.CHCH.sub.2 O(C.sub.2 H.sub.4 O).sub.p --R wherein p is comprised between 5 and 50 and R is C.sub.1 -C.sub.4 alkyl;aliphatic C.sub.3 -C.sub.5 monounsaturated sulfonic acids;compounds of formula ##STR5## wherein: M.sup.+ is as above defined,R.sub.X is H or CH.sub.3,R.sub.XI and R.sub.XII are, independently each from the other H or C.sub.1 -C.sub.8 alkyl,A is NH or N--CH.sub.3 ;said hydrosoluble acrylic polymers contain at the chain ends silanol groups and are obtainable by copolymerizing the monomers in the presence of chain transfer agents selected from the following:--SH--R.sub.o --Si(R.sub.IB).sub.NB (OR.sub.IA).sub.NA (A),whereinR.sub.IA is hydrogen or a saturated C.sub.1 -C.sub.3 alkyl, R.sub.IB is C.sub.1 -C.sub.3 alkyl, NB is an integer and is zero or 1, NA is an integer and is 2 or 3, with the condition that NA+NB=3, R.sub.o is a linear or branched alkylenic chain, containing a number nx of carbon atoms from 1 to 20, optionally containing polar groups bound to the chain directly, or through (CH.sub.2).sub.nx groups, wherein n has the above indicated meaning;a mixture made from compound (A) as above defined with phosphorous.sup.I-III inorganic acid/s or its/their salts, (compound (B)), wherein the phosphorous has an oxidation number varying from I to III (phosphorous.sup.I-III),the cations of the salts of phosphorous.sup.I-III inorganic acids are alkaline, earth-alkaline metals or ammonium ions.