10487-92-0Relevant articles and documents
Synthesis of degradable and chemically recyclable polymers using 4,4-disubstituted five-membered cyclic ketene hemiacetal ester (CKHE) monomers
Ge, Yicen,Goto, Atsushi,Oh, Xin Yi
, p. 13546 - 13556 (2021/10/29)
Novel degradable and chemically recyclable polymers were synthesized using five-membered cyclic ketene hemiacetal ester (CKHE) monomers. The studied monomers were 4,4-dimethyl-2-methylene-1,3-dioxolan-5-one (DMDL) and 5-methyl-2-methylene-5-phenyl-1,3-dioxolan-4-one (PhDL). The two monomers were synthesized in high yields (80-90%), which is an attractive feature. DMDL afforded its homopolymer with a relatively high molecular weight (Mn>100?000, whereMnis the number-average molecular weight). DMDL and PhDL were copolymerized with various families of vinyl monomers,i.e., methacrylates, acrylates, styrene, acrylonitrile, vinyl pyrrolidinone, and acrylamide, and various functional methacrylates and acrylate. Such a wide scope of the accessible polymers is highly useful for material design. The obtained homopolymers and random copolymers of DMDL degraded in basic conditions (in the presence of a hydroxide or an amine) at relatively mild temperatures (room temperature to 65 °C). The degradation of the DMDL homopolymer generated 2-hydroxyisobutyric acid (HIBA). The generated HIBA was recovered and used as an ingredient to re-synthesize DMDL monomer, and this monomer was further used to re-synthesize the DMDL polymer, demonstrating the chemical recycling of the DMDL polymer. Such degradability and chemical recyclability of the DMDL polymer may contribute to the circular materials economy.
Phenyl alpha acyloxyalkanoic acids, derivatives and their therapeutic use
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, (2008/06/13)
Therapeutic as well as preventative measures to improve the cosmetic conditions or to alleviate the symptoms of dermatologic disorders with phenyl alpha acyloxyalkanoic acids and derivatives is disclosed. The cosmetic conditions and dermatologic disorders