Fabrication and performance of fast and reusable pH-sensitive UV-curable silicone modified materials

Determination, control and monitoring the pH valve are quite important for many fields, especially for monitoring the wastewater discharged from chemical industry. Fast and reusable pH-sensitive ultraviolet (UV)curable silicone modified materials with a visible color change in pH conditions of 9.5-14 were prepared by UV initiated thiol-ene reaction with vinyl containing silicone-modified hyperbranched polymers with phenolphthalide (PHP) substitutes and thiol silicone resin. It demonstrated that the UV-curable materials are with transparency higher than 90 %, pencil hardness of F-8 H and Td5 in the range of 310-338 degrees C. The UV-curable materials exhibited an outstanding pH-sensitive property, and they can be used repeatedly about 400 cycles without a faded change of color and loss of sensitivity. What's more, it is interesting when pH value is in the range of 9.5-14, the materials can recognize the organic solvents with different pH values and different volume percentages. The mechanism for the pH-sensitive property was proposed. These materials have potential applications for fabrication quick, reusable and real-time monitoring pH-sensitive devices for alkaline wastewater.

Automated summary

Determination, control and monitoring of pH valve are crucial for various sectors, particularly for monitoring wastewater in the chemical industry. UV-curable silicone modified materials were prepared by UV initiated thiol-ene reaction, which exhibit fast, reusable and pH-sensitive properties with a visible color change in the pH range of 9.5-14. These materials have high transparency, pencil hardness and temperature stability, with the ability to recognize organic solvents with different pH values and percentages. They have potential applications for the fabrication of quick, reusable and real-time pH-sensitive devices for alkaline wastewater.