Ring-opening copolymerization (ROCP) of benzylsulfonyl macroheterocyclosiloxane (BSM) and five different cyclosiloxanes was systematically investigated. A general approach for the synthesis of benzylsulfonyl-containing silicone copolymers with various substituents, including methyl, vinyl, ethyl, and phenyl, was developed herein. A series of copolymers with variable incorporation (from 6 % to 82 %) of BSM were obtained by modifying the comonomer feed ratio and using KOH as the catalyst in a mixed solvent of dimethylformamide and toluene. The obtained copolymers exhibited various composition-dependent properties and unique viscoelasticity. Notably, the surface and fluorescent characteristics as well as the glass transition temperatures of the copolymers could be tailored by varying the amount of BSM. Unlike typical sulfone-containing polymers, such as poly(olefin sulfone)s, the prepared copolymers displayed excellent thermal and hydrolytic stability. The universal strategy developed in the present study provides a platform for the design of innovative silicone copolymers with adjustable structures and performance.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1002/chem.202100309 | DOI Listing |
Macromolecules
November 2024
Materials Department, University of California, Santa Barbara, Santa Barbara, California 93106, United States.
Silicone bottlebrush copolymers and networks derived from cyclic carbosiloxanes are reported and shown to have enhanced properties and recyclability compared with traditional dimethylsiloxane-based materials. The preparation of these materials is enabled by the synthesis of well-defined heterotelechelic macromonomers with Si-H and norbornene chain ends via anionic ring-opening polymerization of the hybrid carbosiloxane monomer 2,2,5,5-tetramethyl-2,5-disila-1-oxacyclopentane. These novel heterotelechelic α-Si-H/ω-norbornene macromonomers undergo efficient ring-opening metathesis copolymerization to yield functional bottlebrush polymers with accurate control over molecular weight and functional-group density.
View Article and Find Full Text PDFPolymers (Basel)
October 2024
College of Material, Chemistry and Chemical Engineering, Key Laboratory of Organosilicon Chemistry and Material Technology, Ministry of Education, Hangzhou Normal University, Hangzhou 311121, China.
Int J Pharm
December 2024
Department of Pharmaceutics, China Pharmaceutical University, Nanjing, Jiangsu 211198, P.R. China. Electronic address:
ACS Appl Mater Interfaces
October 2024
Centre for Additive Manufacturing, Department of Chemical and Environmental Engineering, University of Nottingham, University Park, Nottingham NG7 2RD, United Kingdom.
This study reports the development of the first copolymer material that (i) is resistant to fungal attachment and hence biofilm formation, (ii) operates via a nonkilling mechanism, i.e., avoids the use of antifungal actives and the emergence of fungal resistance, (iii) exhibits sufficient elasticity for use in flexible medical devices, and (iv) is suitable for 3D printing (3DP), enabling the production of safer, personalized medical devices.
View Article and Find Full Text PDFClin Endosc
November 2024
Division of Gastroenterology, Department of Internal Medicine, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
Background/aims: Colonic stenting plays a vital role in the management of acute malignant colonic obstruction. The increasing use of self-expandable metal stents (SEMS) and the diverse challenges posed by colonic obstruction at various locations underscore the importance of effective training for colonic stent placement.
Methods: All the components of the simulator were manufactured using silicone molding techniques in conjunction with three-dimensional (3D) printing.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!