US 11,717,805 B2
Biodegradable high-performance absorbent polymers and methods thereof
Allison Flynn, El Cerrito, CA (US); Harshal Akshay Chokhawala, Castro Valley, CA (US); and Jonathan Carl Pistorino, Oakland, CA (US)
Assigned to ZYMOCHEM, INC., San Leandro, CA (US)
Filed by ZYMOCHEM, INC., Alameda, CA (US)
Filed on Sep. 16, 2022, as Appl. No. 17/947,022.
Application 17/947,022 is a continuation of application No. PCT/US2021/034372, filed on May 26, 2021.
Claims priority of provisional application 63/030,266, filed on May 26, 2020.
Prior Publication US 2023/0058841 A1, Feb. 23, 2023
Int. Cl. B01J 20/26 (2006.01); C08G 81/02 (2006.01); B01J 20/28 (2006.01); A61L 15/26 (2006.01); C08G 63/12 (2006.01); A61L 15/60 (2006.01)
CPC B01J 20/267 (2013.01) [A61L 15/26 (2013.01); B01J 20/28004 (2013.01); B01J 20/28016 (2013.01); C08G 63/12 (2013.01); A61L 15/60 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method for making crosslinked γ-polyglutamic acid absorbent configured for use as part of a diaper, the method comprising:
providing γ-polyglutamic acid before crosslinking having an Mn of about 0.6-0.7 million Da when assessed using HPLC using size exclusion chromatography (SEC) using UV and/or refractive index (IR) detectors;
crosslinking γ-polyglutamic acid with sorbitol polyglycidyl ether to provide crosslinked γ-polyglutamic acid absorbent, wherein the amount of sorbitol polyglycidyl ether during crosslinking is about 1-3% of the total weight of γ-polyglutamic acid and sorbitol polyglycidyl ether;
wherein the resulting crosslinked γ-polyglutamic acid absorbent has an absorption under load (AUL) of about 10 to 50 g/g under 0.7 psi when assessed according to ISO 17190-7, and a centrifugal retention capacity (CRC) of about 20 to 50 g/g when assessed according to ISO 17190-6.