α-cyanoacryloyloxyethyloxypropyl-functionalized polysiloxanes were prepared using a condensation reaction between the adduct of anthracene/α-cyanoacryloyl chloride and hydroxyethyloxypropyl-modified polydimethylsiloxanes, followed by a retro-Diels-Alder reaction to deprotect the anthracene. Structures of the obtained polymers and their intermediates were characterized using 1 H NMR, 13 C NMR, and FT-IR spectroscopies. Under mild conditions such as at room temperature with a relative humidity of 60%, the α-cyanoacryloyloxyethyloxypropyl-functionalized polysiloxanes could be completely cured within 3 minutes. With a small amount of N,Ndimethyl-p-toluidine as the initiator, the curing time could be further shortened to 3-5 seconds. Various factors affected on the cross-linking density and the average molecular weight between two adjacent cross-linking points were investigated. The results indicated that with the introduction of the α-cyanoacryloyloxyethyloxypropyl group, α-cyanoacryloyloxyethyloxypropylfunctionalized PDMS exhibited much better thermal stabilities than that of pure poly(ethyl α-cyanoacrylate). Besides, the introduction of an αcyanoacryloyloxyethyloxypropyl group in the PDMS molecule also eliminated the crystallization behavior and glass transition temperature of PDMS. The results of the water contact angle test showed the interfacial characteristics of the prepared material changed significantly relative to pure PDMS. With the increase in the content of the functional group, the water contact angle of the material showed an overall increasing trend.

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α‐Cyanoacryloyloxyethoxypropyl‐functionalized MQ resins were synthesized using commercially available hydrogen‐containing MQ silicone resin and 2‐(allyloxy)ethoxytrimethylsilane through a series of hydrosilylation, condensation and retro‐Diels‐Alder reactions. Under the conditions of room temperature and relative humidity of 60 %, the prepared silicone resins could be completely cured within 10 h without adding any promoters. When a small amount of N, N‐dimethyl‐p‐toluidinewas added as an accelerator, the curing time could be shortened to 3–5 s. Although grafted α‐cyanoacryloyloxyethoxypropyl groups on MQ resins reduced their thermal stabilities, the introduction of α‐cyanoacryloyloxyethoxypropyl groups destroyed the order of polysiloxane segments and eliminated the crystallization behavior of polysiloxane, which is beneficial to maintain structural stability of the functionalized polysiloxanes over a wide temperature range. The water contact angle of the cured product decreased from 102° to approximately75° when α‐cyanoacryloyloxyethoxypropyl groups were grafted to the polysiloxaneand thus changed the hydrophobicity of the polydimethylsiloxane materials to hydrophilicity. The novel α‐cyanoacryloyloxyethoxypropyl‐functionalized MQ resins not only maintain the inherent flexibility of polysiloxanes but also endow the silicone materials with the characteristics of fast cross‐linking.

MT‐type polysiloxanes containing active vinyl group were prepared under acid conditions initiated from divinyltetramethyldisiloxane and methyltrimethoxysilane by one‐pot method, co‐hydrolysis method, and reaction‐rectification coupling method, respectively. The influence of different methods on molecular weight, molecular weight distribution, and ratios of each kind of segment in the MT‐type polysiloxane containing active vinyl group were discussed in detail. The results indicated that with the reaction‐rectification coupling method, the residual hydroxyl segment in the prepared MT‐type polysiloxane could be lower than 0.5 wt%. For MT‐type polysiloxanes with high hydroxyl group content, the hydroxyl content could be reduced when treated with hexamethyldisilazane, trimethylchlorosilane, zinc naphthalate, or tetramethylammonium hydroxide under suitable conditions. Hexamethyldisilazane was the most convenient and effective regents among these four compounds, the residual hydroxyl content contained in the prepared MT‐type polysiloxanes could be reduced from 13.4 to 0.9 wt% when MT‐type polysiloxane sample was treated with hexamethyldisilazane.