Patent ID: 7981970
Filing Date: 2011-07-19
Classification: A61F,B01D,C08F,H01M,Y02E,Y10T

Abstract:
1. A sulfonated block copolymer comprising at least two polymer end blocks A, at least one polymer interior block B wherein: a. each A block is a polymer block resistant to sulfonation and each B block is a polymer block susceptible to sulfonation, said A and B blocks containing no significant levels of olefinic unsaturation; b. each A block independently having a number average molecular weight between 1,000 and 60,000 and each B block independently having a number average molecular weight between 10,000 and 300,000; c. each A block comprising one or more segments selected from polymerized (i) acrylic esters, (ii) methacrylic esters, and (viii) mixtures thereof; d. each B block comprising segments of one or more vinyl aromatic monomers selected from polymerized (i) unsubstituted styrene monomers, (ii) ortho-substituted styrene monomers, (iii) meta-substituted styrene monomers, (iv) alpha-methylstyrene, (v) 1,1-diphenylethylene, (vi) 1,2-diphenylethylene and (vii) mixtures thereof; e. said B blocks are sulfonated to the extent of 10 to 100 mol percent, based on the units of vinyl aromatic monomer in said B blocks; and f. the mol percent of vinyl aromatic monomers which are unsubstituted styrene monomers, ortho-substituted styrene monomers, meta-substituted styrene monomers, alpha-methylstyrene, 1,1-diphenylethylene and 1,2-diphenylethylene in each B block being between 10 mol percent and 100 mol percent; and g. said sulfonated block copolymer is non-dispersible and solid in water at neutral pH, and has a tensile strength greater than 100 psi in the presence of water according to ASTM D412 after immersion in water for 24 hours.