Abstract: A hydrophilic, highly swellable hydrogel based on (co)polymerized monomers or based on graft (co)polymers and prepared by
a) free-radically (co)polymerizing one-or more hydrophilic monomers or graft (co)polymerizing one or more hydrophilic monomers onto a grafting base, the average degree of neutralization of the acid-functional monomers being from 0 to 40 mol %,
b) comminuting the acidic hydrogel,
c) neutralizing the acidic hydrogel to an ultimate degree of neutralization of 50-85 mol % by adding a neutralizing agent,
d) drying, grinding and sieving the hydrogel particles characterized by
a centrifuge retention and a vertical absorption swell height, each having a specified minimum.value, coupled with an extractables content having a specified maximum value or
a centrifuge retention and a vertical absorption swell height, each having a specified minimum value and
an extractables content having a specified maximum value.
Type:
Grant
Filed:
April 6, 2001
Date of Patent:
August 5, 2003
Assignee:
BASF Aktiengesellschaft
Inventors:
Joachim Dentler, RĂ¼diger Funk, Norbert Herfert, Mariola Wanior, Friedrich Engelhardt
Abstract: Cellulosic polymers, copolymers and grafts, are disclosed that adhere to fibers and surfaces during an aqueous treatment process. The cellulosic polymers having grafts and/or co-blocks are prepared using living-type free radical polymerization techniques, which provides control over the degree of substitution and graft/co-block composition and structure. These cellulosic polymers allow for the modification of fibers and surfaces to provide a desired effect.
Type:
Grant
Filed:
July 20, 2001
Date of Patent:
July 22, 2003
Assignee:
Symyx Technologies, Inc.
Inventors:
Dominique Charmot, Manikandan Jayaraman, Han Ting Chang, Paul Mansky, Wilfried Blokzijl
Abstract: A hydrogel forming system which comprises a hydrophobic macromer with unsaturated group terminated ends and a hydrophilic polymer which is a polysaccharide (e.g., dextran) containing hydroxy groups which are reacted with unsaturated group introducing compound, is convertible by free radical polymerization to form a hydrogel containing a three dimensional crosslinked polymer network containing hydrophobic and hydrophilic components. Agent can be entrapped in the polymer network, e.g., drugs, macromolecules or synthetic or natural polymers, for controlled release therefrom.
Abstract: Cellulosic polymers, copolymers and grafts, are disclosed that adhere to fibers and surfaces during an aqueous treatment process. The cellulosic polymers having grafts and/or co-blocks are prepared using living-type free radical polymerization techniques, which provides control over the degree of substitution and graft/co-block composition and structure. These cellulosic polymers allow for the modification of fibers and surfaces to provide a desired effect.
Type:
Application
Filed:
July 20, 2001
Publication date:
May 15, 2003
Inventors:
Dominique Charmot, Manikandan Jayaraman, Han Ting Chang, Paul Mansky, Wilfried Blokzijl
Abstract: Poly(ethylene glycol) (PEG), a highly biocompatible hydrophilic polyether, is tethered to poly(propylene fumarate) (PPF), a biodegradable polyester. To avoid change in molecular weight distribution of PPF, end hydroxyl groups of PPF are reacted with bis-carboxymethyl PEG after being treated with thionyl chloride. New end carboxyl groups of the PEG-tethered PPF are further reacted with N-hydroxysuccinimide (NHS) in the presence of dicyclohexylcarbodiimide (DCC) to couple bioactive molecules. Glutamine and glycine-arginine-glycine-aspartic acid (GRGD) are attached to the PEG-tethered PPF in 50 mM phosphate buffer of pH of 7.4. The method is valuable for the preparation of a triblock copolymer with PEG end blocks and the coupling of biologically active molecules.