23-11-2017 дата публикации
Номер: US20170335514A1
Принадлежит:
A method for controlling the deposition of stickies in pulping and papermaking processes comprises adding to fibre pulp or stock an additive comprising an organo-modified siloxane comprising units of the formula: [RZSiO]in which each Ris independently selected from a hydrogen atom, an alkyl, aryl, alkenyl, aralkyl, alkaryl, alkoxy, alkanoyloxy, hydroxyl, ester or ether group, and each Z is independently selected from an alkyl group substituted with an amine, amide, carboxyl, ester, or epoxy group, or preferably at least one or more groups —R—(OCH)(OCH)—R; wherein n is an integer greater than 1; a and b are independently 0, 1, 2 or 3; Ris an alkylene group or a direct bond; Ris a group as defined for Ror Z above; p and r are independently an integer from 1 to 6; q and s are independently 0 or an integer such that 1≦q+s≦400; and wherein each molecule of the organo-modified siloxane contains at least one group Z. The organo-modified siloxane is preferably a hydroxyl- or alkyl-endcapped linear polydimethylsiloxane, in which 5 to 18 mole percent of silicon atoms are substituted by Z groups of the formula —R—(OCH)(OCH)—R, in which p is 2, r is 3 and q and s are independently 10 to 20, Ris an alkylene group having from 1 to 6 carbon atoms or a direct bond, and Ris a hydrogen atom or a hydroxyl, alkoxy, ester or ether group. 1. A method for controlling the deposition of stickies in pulping and papermaking processes which comprises adding to fibre pulp or stock an additive comprising an organo-modified siloxane comprising units of the formula:{'br': None, 'sup': '1', 'sub': a', 'b', '(4-a-b)/2', 'n, '[RZSiO]'}{'sup': '1', 'in which each Ris independently selected from a hydrogen atom, an alkyl, aryl, alkenyl, aralkyl, alkaryl, alkoxy, alkanoyloxy, hydroxyl, ester or ether group;'}{'sup': 2', '3, 'sub': p', 'p', 'q', 'r', '2r', 's, 'each Z is independently selected from an alkyl group substituted with an amine, amide, carboxyl, ester, or epoxy group, or a group —R—(OCH)(OCH)— ...
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