Gerald K. Schalau

Recent advances in silicone pressure-sensitive adhesives

Silicone pressure-sensitive adhesives (PSAs) are widely used in pressure-sensitive tapes and labels when application conditions or the nature of substrate surfaces surpass the performance boundaries of organic-based PSAs. Since the year 2000, there has been continuing interest in and pursuit of new uses for silicone PSAs, especially in applications such as medical and industrial tapes. Driven by needs for regulatory compliance and changing performance requirements, silicone PSAs based on new silicone chemistry and cure mechanisms have also emerged. This paper reviews significant advances that have occurred over the past decade in the field of silicone PSAs and describes the range of commercial uses where silicone PSAs are being used and exploited. These include industrial, electronics and medical applications.

Silicone Excipients in Pharmaceutical Drug Delivery Applications

Silicones have been used in medicines, cosmetics and medical devices for over 60 years. Polydimethylsiloxanes (PDMS) are commonly used as an active in many oral antiflatulent remedies and topically applied skin protectant creams, and ointments. The plethora of physical forms and the physio-chemical properties that silicones can display has led to their adoption in a diverse array of healthcare applications in different physical forms including as excipients in topical and transdermal drug delivery systems. Unique characteristics like hydrophobicity, low surface tension, and aesthetics intrinsically associated with silicones offer function and performance to drug delivery products. Recent research investigations support the use of silicone based pressure sensitive adhesives for their skin-friendliness, and also to enhance the efficacy of the drug in the transdermal drug delivery patch products. Similarly, in topical drug delivery applications, silicone based novel excipients have demonstrated their capability in improving drug delivery efficiency. Recent silicone technologies like swollen crosslinked silicone elastomer blend networks, sugar siloxanes, amphiphilic resin linear polymers, and silicone based hybrid pressure sensitive adhesives promise potential performance advantages and improved drug delivery efficacy in topical or transdermal drug delivery systems.