Low Cost Solution Processing Disulfide Glass Prepolymers from Sulfenyl Chlorides

A novel soluble prepolymer has been developed through the reaction of sulfur monochloride (S2Cl2) with 1,3,5-triallylisocyanurate (TIC). This technology is a novel method which yields a highly functional, low-cost branched polymer suitable for various thin film applications, including high refractive index coatings, transparent coatings, negative tone photoresists, optical adhesives, optical coatings, and photoresist platters. This innovation builds on existing sulfenyl chloride materials, originally developed for crosslinked, thermoset bulk optical glass lenses. This new material, referred to as "disulfide glass," offers exceptional transparency and a high glass transition temperature. This method allows for the creation of pre-polymers from this disulfide glass that are not crosslinked, allowing for their use in coatings and other thin film applications. By adding triallyl isocyanurate, the process yields a soluble branched prepolymer with numerous vinyl-allyl groups that can be crosslinked using various methods like heat, UV light, or photolithography. This breakthrough results in the ability to produce polymer products with excellent optical and thermomechanical properties at a lower cost, replacing materials like SU8 in microelectronics fabrication. 

Background: 
Polymerizations of sulfur monochloride and triallyl isocyanurate have already been shown to yield disulfide glasses with outstanding optical qualities superior to other plastics. The technology is addressing the need for high-quality optical materials that can be used in various applications, particularly in microelectronics fabrication. Current solutions often involve materials like SU8, a commonly used photoresist, which have limitations in terms of cost, optical properties, and processability. SU8 and similar materials can be expensive, have limited transparency, and may not be easily processed into thin films or coatings.. The new technology offers a significant improvement over current solutions by providing a highly transparent, thermally stable material that can be processed into thin films and coatings. This "disulfide glass" is formed from sulfur monochloride and triallyl isocyanurate, and it offers excellent optical qualities at a lower cost compared to traditional materials. 

Applications: 

• Microelectronics fabrication
• Optical coatings and thin films
• Lithography
• Medical devices

Advantages:

• Lower cost compared to traditional materials 
• Improved optical properties, offering higher transparency
• Processable into thin films and coatings, providing versatility in application
• Thermally stable, suitable for various environments
• Can be crosslinked using multiple methods, allowing for customizable properties
• Potential for direct waveguide patterning, expanding its utility in optical applications