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Development of bio-based vitrimers attracted significant attention due to these species’ excellent recyclability and renewability. However, most bio-based vitrimers require high-temperature curation and catalyst use. Herein, room temperature-curable vanillin-based vitrimers were prepared via a catalyst-free route involving a Schiff base reaction and an amino–yne click reaction; the obtained vitrimers exhibited excellent recyclability and high degradability under mild conditions. The chemical structures, mechanical properties, and thermal stability of the obtained crosslinked networks were characterized in detail. These networks displayed good malleability performance, reflected by values for the glass transition temperature of 55–62 °C, tensile strength of 13–15 MPa, and elongation at break of 77–98%. Notably, the vitrimer networks exhibited recyclability due to the multifunction dynamic exchange reactions of Schiff base network and enamine–one network (amino–yne click reaction). More interestingly, these vitrimers could be completely degraded in mild organic acid, organic base, and amine solutions.

Polysiloxanes having 3,3,3-trifluoropropyl (TFP) groups attached to the silicon atom are highly attractive by virtue of their unique properties such as extreme solvent resistance and broad service temperatures. Though fluoroalkylsiloxane polymers are known for their resistance to hydrocarbon solvents and oils, reports on room temperature curable fluoroalkylsiloxane polymer based coatings that are resistant to corrosive acidic and oxidative environments are very rare. In this paper, for the first time, we report the synthesis of vinyl terminated fluorosilicone copolymer, poly(methyltrifluoropropyl- co -methylvinyl) siloxane (V-PFMVS) with very high TFP content (77 mol%) and 23 mol% vinyl content, and its comparison of properties with non-fluorinated counterpart, vinyl terminated poly(dimethyl- co -methylvinyl) siloxane (V-PDMVS). The synthesised copolymers were obtained in high yields of 70–75% with number average molecular weight (M n ) of 65,000 and were cured using cyclic hydridosiloxane via hydrosilylation route. Cured V-PFMVS exhibited increased hydrophobicity compared to cured V-PDMVS (contact angle 113° vs . 91°). The corresponding silica reinforced composites also were processed and evaluated for dynamic mechanical and thermal properties as well as response to various environments including hexane, conc. HNO 3 and HF. Swelling studies proved the role of -CH 2 CH 2 CF 3 groups in imparting excellent resistance to hexane and better resistance to corrosive acidic environments as illustrated by the low weight loss after exposure to conc. HNO 3 and HF in the case of V-PFMVS/composite. Lap shear strength (LSS) evaluation on aluminium substrate proved its capability as a promising adhesive. The superior properties of the V-PFMVS/composite are correlated to its chemical composition. [ABSTRACT FROM AUTHOR]

Development of bio-based vitrimers attracted significant attention due to these species' excellent recyclability and renewability. However, most bio-based vitrimers require high-temperature curation and catalyst use. Herein, room temperature-curable vanillin-based vitrimers were prepared via a catalyst-free route involving a Schiff base reaction and an amino–yne click reaction; the obtained vitrimers exhibited excellent recyclability and high degradability under mild conditions. The chemical structures, mechanical properties, and thermal stability of the obtained crosslinked networks were characterized in detail. These networks displayed good malleability performance, reflected by values for the glass transition temperature of 55–62 °C, tensile strength of 13–15 MPa, and elongation at break of 77–98%. Notably, the vitrimer networks exhibited recyclability due to the multifunction dynamic exchange reactions of Schiff base network and enamine–one network (amino–yne click reaction). More interestingly, these vitrimers could be completely degraded in mild organic acid, organic base, and amine solutions. • Room temperature curable and catalyst-free vanillin-based vitrimer networks were prepared. • The obtained vitrimers exhibited excellent recyclability and high degradability under mild conditions. • The vitrimer networks exhibited recyclability due to the multifunction dynamic exchange reactions. • These vitrimers could be completely degraded in mild organic acid, organic base, and amine solutions. [ABSTRACT FROM AUTHOR]