Polymer product in particle form and its use
AssigneeKemira Oyj
InventorsAsko Karppi, Matti Hietaniemi, Anneli Lepo, Kimmo Strengell
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Abstract
The invention relates to a water-soluble polymer product in particle form, comprising amphoteric polyacrylamide, which is obtained by gel polymerisation of acrylamide together with anionic and cationic monomers. The amphoteric polyacrylamide has a mass average molecular weight MW of 1 500 000-6 000 000 g/mol, and a total ionicity of 4-15 mol-%, whereby the polymer product has a polymer content of at least 60 weight-%. The invention relates also to uses of the polymer product in paper and board making.
Claims18
A water-soluble polymer product in a particle form, comprising:
- amphoteric polyacrylamide obtained by gel polymerisation of acrylamide together with anionic and cationic monomers, and which amphoteric polyacrylamide has:
- a mass average molecular weight MW in a range of 2,500,000-4,500,000 g/mol, and
- a total ionicity of 4-15 mol-%,
- wherein the polymer product has a polymer content of at least 60 weight-%.
A method for treating a fibre stock in paper and/or board making, the method comprising:
- dissolving the water-soluble polymer product in a particle form according to claim into water, whereby an aqueous treatment solution is obtained,
- adding the obtained treatment solution to the fibre stock, and
- forming a fibrous web.
Dependencies are inferred from the claim text.