http://rdf.ncbi.nlm.nih.gov/pubchem/patent/DE-4203818-A1
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_b1a8f92c331b255c0b42b829ccd90cd0 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C08F226-04 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C08F220-56 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08F4-28 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08F226-04 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08F2-32 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C08F220-56 |
| filingDate | 1992-02-10-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| inventor | http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_54177febc81adefda039a13be4e2853b http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_39902575ee1a175d24ac25adb69178c2 |
| publicationDate | 1992-08-20-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | DE-4203818-A1 |
| titleOfInvention | IMPROVED DADMAC / ACRYLAMIDE COPOLYMERS AND METHOD FOR THEIR PREPARATION |
| abstract | Synthesis of copolymer (I) of diallyl-dimethyl-ammonium chloride (DADMAC) and acrylamide, with improved incorporation of DADMC monomer involves (a) prodn. of a water-in-oil emulsion contg. 30-40 wt.% hydrocarbon oil, 25-40 wt. % water, 0-10 wt. % acrylamide, 10-30 wt. % DADMAC, 0.5-2.0 wt. % 2-10C organic acids (or salts), 0.01-0.1 wt. % formic acid (or salts) and 2.5-20.0 wt. % emulsifier with HLB value 4.0-7.0, capable of producing emulsions with mean particle size of 0.5-2.5 microns, (b) producing an initial monomer emulsion by homogenising these components until the particle size is in the above range, (c) heating to 30-80 deg.C under inert gas to obtain an oxygen-free emulsion, (d) addn. polymerising a free-radical catalyst, (e) adding a 40-60 wt. % aq. soln. of acrylamide, continuously or in portions, so as to maintain a constant ratio of unreacted DADMAC to unreacted acrylamide, (f) completing polymerisation for a further 2 hours. at 70 deg.C, after the initial concn. of unreacted DADMAC has decreased by at least 80% and then (g) isolating or sepg. the copolymer (I) from the emulsion which contains 0-500 ppm acrylamide and 0.1-4.5 wt. % unreacted DADMAC. Pref. an oil-soluble radical catalyst is used in (d) and, in stage (f), a satd. aq. soln. of (NH4)2S2O8 is added as catalyst, followed by at least an equiv. amt. of Na2S2O5; during stage (e), the mol. ratio (unreacted DAMAC): (unreacted acrylamide) is kept at a value in the range of 2-300, pref. 3-100, with pref. initial mol. ratio = 2-300; organic acid component is adipic, maleic, fumaric, acetic and/or citric acid, and emulsifier is Mackamide NOA and/or Schercomid SO-A (RTM), pref. with addn. of a poly-soap. Pref. catalyst are azo cpds. or peroxides in stage (d) and the above redox system in stage (f); poly-soa is, e.g. stearyl methacrylate/methacrylic acid copolymer; pref. reaction temp. is 65-80 deg.C. USE/ADVANTAGE - Process enables better incorporation (i.e. up to 94-95%) of DADMAC in copolymerisation with more reactive comonomers, to give copolymers with a lower content of unreacted |
| isCitedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-5750781-A http://rdf.ncbi.nlm.nih.gov/pubchem/patent/EP-0688800-A1 |
| priorityDate | 1991-02-13-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 54.