High molecular weight poly(dially dialkyl) ammonium salts
OwnerZhiqiang Song, George William Schriver +1inventors
InventorsZHIQIANG SONG, George William Schriver, Holger Reinicke
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Abstract
The invention is directed to a method of making ultra high molecular weight diallyldialkyl ammonium salt homopolymers, compositions thereof and use of compositions as a fixative in papermaking.
Claims10
A diallyldialkyl ammonium salt homopolymer formed by the method comprising the steps:
- i) preparing an aqueous monomer phase containing a monomer of diallyldialkyl ammonium salt,
- a radical initiator or mixture of radical initiators,
- and
- optionally a chelating agent,
- ii) heating the aqueous monomer phase formed in step i) at temperature(s) below about 60° C. to a monomer conversion to homopolymer from about 80 to about 99 wt. %, wherein substantially all the initiator is added in step i) or before heating in step ii) and the initiator concentration is about 0.1 to about 5.0 wt. % based on the monomer,
- and
- iii) then post treating the formed homopolymer by heating to a temperature in the range from about 60 to about 120° C.
A bead comprising a ultra high molecular weight homopolymer of diallyldialkyl ammonium salt monomer having an intrinsic viscosity in 1M NaCl aqueous solution at 30° C. of above 2.0 dL/g or a bulk viscosity at 1% polymer concentration in water and at 25° C. (1% BV) of above 20 cps.
A bead comprising a homopolymer of diallyldialkyl ammonium salt monomer, wherein the homopolymer has incorporated at least about 95 wt. % of the diallyldialkyl ammonium salt monomer into the homopolymer.
Dependencies are inferred from the claim text.