Impressive Rate Raise of the Hydrosilation Reaction Through UV‐Activation: Energy and Time Saving

Abstract

Silicone materials are widely used in many fields such as electrical or food industries and their consumption is constantly growing. They are generally cured by vulcanization reaction for long time at high temperatures which requires high energy consumption. The possibility to achieve the polymerization of silicone rubbers by UV‐activation promotes the reduction of both time and temperature leading to an impressive energy saving. Indeed, this process is more than 30 times faster than the thermal one. Moreover, the properties of the two resulting materials are comparable, indicating that the low time of UV‐activated hydrosilation reaction is suitable for the formation of crosslinked silicone polymers.

Fifty Years of Hydrosilylation in Polymer Science: A Review of Current Trends of Low-Cost Transition-Metal and Metal-Free Catalysts, Non-Thermally Triggered Hydrosilylation Reactions, and Industrial Applications

“…Hence, the photocatalytic hydrosilylation of electron-poor alkenes could be performed. The reactions could be Marchi and coworkers demonstrated in how far (in terms of energy and time saving) photo-activation is the favorable way for (crosslinking) hydrosilylation catalysis employing Pt II (acac) 2 as catalyst [91]. They used the catalyst for photo-and thermal activation and monitored the silane conversion at various temperatures.…”

UV‐activated hydrosilylation of (Me‐Cp)Pt(Me)3: Enhanced photocatalytic activity, polymerization kinetics, and photolithography

“…For better durability and reliability, they should be vulcanized to form a three‐dimensional crosslinked network via polycondensation at room temperature or hydrosilylation or peroxide reaction at high temperature . However, these curing methods have long been considered as a seriously time‐consuming and energy‐intensive process . Under the uptrend of sustainable development, UV‐curing or photopolymerization technology has recently attracted extensive interest because of its fast rate, high efficiency, energy conservation, and environmental friendliness …”

“…Herein, Pt(acac) 2 and (Me‐Cp)Pt(Me) 3 are the predominant cases. It has demonstrated that the photopolymerization rate of hydrosilylation catalyzed by Pt(acac) 2 is 30‐fold faster than thermopolymerization, while (Me‐Cp)Pt(Me) 3 complex presents a much higher photochemical reactivity than Pt(acac) 2 . However, the photopolymerization mechanism and kinetics of photoactivated hydrosilylation has not been clearly disclosed.…”

Light-Triggered Radical Silane-Ene Chemistry Using a Monosubstituted Bis(trimethylsilyl)silane

“…Silane‐ene chemistry has been proposed as a further potential candidate by implementing silanes with abstractable hydrogens. Additionally, such silanes are also of significant interest for photografting applications on silicon surfaces and in silicon polymer science . With the establishment of a working silane‐ene system, radical oxygen inhibition could possibly be prevented .…”

“…Additionally, such silanes are also of significant interest for photografting applications on silicon surfaces [17] and in silicon polymer science. [18] With the establishment of a working silane-ene system, radical oxygen inhibition could possibly be prevented. [19] New reactive silanes could also be used as radical reducing agents [20] or type II coinitiators.…”