Cellulose-based hybrid glycosilicones via grafted-to metal-catalyzed hydrosilylation: “When opposites unite”

• Published in: Carbohydrate polymers 2020-08, Vol.241, p.116327, Article 116327
• Main Authors: Dobrynin, Mikhail V., Kukushkin, Vadim Yu, Islamova, Regina M.
• Format: Article
• Language: English
• Subjects: Catalysis; Cellulose - analogs & derivatives; Cellulose - chemical synthesis; Cellulose - chemistry; Chlorella vulgaris; Dimethylpolysiloxanes - chemical synthesis; Dimethylpolysiloxanes - chemistry; Glycosilicone; Hydride-terminated polysiloxane; Hydrosilylation; Karstedt’s catalyst; Paramecium caudatum; Propargylated hydroxyethyl cellulose; Rh(acac)(CO)2; Toxicity Tests
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2020.116327

[Display omitted] •Cellulose-based glycosilicones via catalytic hydrosilylation.•Rhodium- and platinum-catalyzed hydrosilylation toward glycosilicone synthesis.•The grafting degree was controlled by means of catalyst choice and reagent load.•Hydrosilylation leads to less toxic glycosilicones than click-chemistry approach. Hydrosilylation catalyzed by the rhodium(I) complex [Rh(acac)(CO)2] or platinum(0)-based Karstedt’s catalyst was employed to combine hydrophilic propargylated hydroxyethyl cellulose and hydrophobic hydride-terminated polydimethylsiloxane to give polymer hybrid structures. The final polymers were characterized by FTIR, solid state 1H, 13C and 29Si NMR, contact angle, microcalorimetry and thermogravimetry measurements. The grafting degree was controlled by the catalyst choice and by the reagent load variations; an increase of the polysiloxane load and a change from Karstedt’s to the rhodium catalyst led to a higher (from 2 to 7%) silicon content in the glycosilicones. The glycosilicones were insoluble in water, but swelled in organic solvents (DMSO, DMF, and chloroform). The hydrophilicity of the glycosilicones decreased with incrementing silicon content: the contact angles increased from 30 (cellulose) to 103–131° in the hybrids. The glycosilicones obtained via the hydrosilylation are less toxic toward algae Chlorella vulgaris and infusoria Paramecium caudatum than those obtained with CuAAC.