TY - JOUR
T1 - Renewable (Bis)pyrrolidone Based Monomers as Components for Thermally Curable and Enzymatically Depolymerizable 2-Oxazoline Thermoset Resins
AU - Roy, Manta
AU - Noordzij, Geert J.
AU - Van Den Boomen, Yara
AU - Rastogi, Sanjay
AU - Wilsens, Carolus H.R.M.
N1 - Generated from Scopus record by KAUST IRTS on 2021-02-16
PY - 2018/4/2
Y1 - 2018/4/2
N2 - In this study we describe the synthesis of bis(pyrrolidone) based dicarboxylic acids from itaconic acid and their application in 2-oxazoline resins for fully renewable thermoset materials. The monomers are obtained using a bulk aza-Michael addition of a diamine and two itaconic acid molecules using a catalytic amount of water. The monomers can be isolated in high purity after recrystallization, though their yield proved to be highly dependent on the selected diamine spacer length: In general, only the dicarboxylic acids containing diamines with an even number of methylene spacers are isolated in high yields. Through NMR, GPC, and FTIR analysis we demonstrate that these bis(pyrrolidone) based dicarboxylic acids exhibit significantly enhanced curing rates in 2-oxazoline resins compared to resins containing aliphatic dicarboxylic acids such as sebacic acid. Overall, we demonstrate that the rate of 2-oxazoline ring-opening addition with carboxylic acid functionalities is determined by the used dicarboxylic acid, whereas the ring-opening addition of the 2-oxazoline functionality with amide groups is determined by the used bis(2-oxazoline) compound. The thermosets obtained after curing proved to be readily plasticized by water, opening up possibilities for enzymatic degradation.
AB - In this study we describe the synthesis of bis(pyrrolidone) based dicarboxylic acids from itaconic acid and their application in 2-oxazoline resins for fully renewable thermoset materials. The monomers are obtained using a bulk aza-Michael addition of a diamine and two itaconic acid molecules using a catalytic amount of water. The monomers can be isolated in high purity after recrystallization, though their yield proved to be highly dependent on the selected diamine spacer length: In general, only the dicarboxylic acids containing diamines with an even number of methylene spacers are isolated in high yields. Through NMR, GPC, and FTIR analysis we demonstrate that these bis(pyrrolidone) based dicarboxylic acids exhibit significantly enhanced curing rates in 2-oxazoline resins compared to resins containing aliphatic dicarboxylic acids such as sebacic acid. Overall, we demonstrate that the rate of 2-oxazoline ring-opening addition with carboxylic acid functionalities is determined by the used dicarboxylic acid, whereas the ring-opening addition of the 2-oxazoline functionality with amide groups is determined by the used bis(2-oxazoline) compound. The thermosets obtained after curing proved to be readily plasticized by water, opening up possibilities for enzymatic degradation.
UR - https://pubs.acs.org/doi/10.1021/acssuschemeng.7b04716
UR - http://www.scopus.com/inward/record.url?scp=85044748536&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.7b04716
DO - 10.1021/acssuschemeng.7b04716
M3 - Article
SN - 2168-0485
VL - 6
SP - 5053
EP - 5066
JO - ACS Sustainable Chemistry and Engineering
JF - ACS Sustainable Chemistry and Engineering
IS - 4
ER -