WACKER presents its silicone adhesive gels and liquid silicone rubber for medical applications at the medical technology trade show COMPAMED.
SILPURAN® silicone adhesives have a track record as adhesive gels in professional wound dressings over many years. They adhere gently and securely to the skin and make changing dressings pain-free and atraumatic. This promotes healing while allowing gentle treatment of chronic and large-area wounds.
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SILPURAN® 2114 & SILPURAN® 2122 Silicone Adhesive Gels
At COMPAMED 2021, the spotlight is on SILPURAN® 2114 and SILPURAN® 2122. As these silicone gels adhere strongly, they can be used for professional wound treatment as well as for fixing plasters for longer-term positioning of dressings and medical devices.
SILPURAN® 2114 offers an adhesive strength of 3.5 Newton per inch and is thus the product of choice for plasters and wound dressings. SILPURAN® 2122 features even stronger adhesion: with an adhesive strength of 5.5 Newton per inch, the silicone gel can also be used as a fixing aid in wearables and other medical applications. With SILPURAN® 2122, base plates for colostomy bags, wearable sensors or dosing devices for dispensing medication can be gently and reliably fixed on the skin.
SILPURAN® 2114 and SILPURAN® 2122 are transparent and cure to form a soft, highly flexible material with a gel consistency. The silicone gel itself is water-repellent, but breathable due to its permeability to water vapor and gas, optimizing wound healing significantly. The products contain neither plasticizers nor stabilizers. They are chemically stable, aging resistant and can be readily sterilized with ethylene oxide.
The gels are efficient in terms of usage. In most cases, only small amounts is required for positioning of wound dressings or plasters. Moreover, fixation aids that have been coated with SILPURAN® 2114 and SILPURAN® 2122 can also be easily stripped off and reapplied. An incorrectly bonded fixation plaster still adheres reliably to the skin even after correction.
Optimum Combination of Release Film and Silicone Adhesive
Wound dressings and fixation aids are generally supplied with release liners. They protect the adhesive layer against soiling and damage and are removed when used. However, high-strength adhesives can cause problems when, for example, the adhesive film is damaged as the liner is peeled off.
To ensure safe removal, WACKER coated several liners produced by US manufacturer Loparex with SILPURAN® 2114 and SILPURAN® 2122 and examined their release properties. The tests show that SILPURAN® 2114 can be readily used with selected poly-olefine liners, while SILPURAN® 2122 performs best with fluorinated substrates. In all cases, the release force was below 0.5 N/in, which ensures reliable and complete removal of the liner. The long-term measurements WACKER conducted also speak for themselves: despite several months’ storage, no increase of the release force values were measured. Wound dressings and fixation aids coated with SILPURAN® 2114 and SILPURAN® 2122 thus exhibit a long shelf life.
ELASTOSIL® LR 5040 – Liquid Silicone Rubber for Sensitive Applications
WACKER is also presenting the ELASTOSIL® LR 5040 product line at COMPAMED. This liquid silicone rubber (LSR) meets strict regulatory specifications which apply to sensitive applications in medical and food-contact segments. Cured rubber products made of ELASTOSIL® LR 5040 feature excellent mechanical properties even without thermal postcuring and contain only very little amounts of volatile and extractable substances. This allows manufacturers, in many cases, to eliminate postcuring during the production process.
ELASTOSIL® LR 5040 cures to a translucent elastomer whose volatiles content is below 0.5 weight percent without thermal post-treatment. This was determined by in-house measurements following German Institute for Risk Assessment (BfR) procedures using two millimeter-thick LSR sheets heated up to 200°C for four hours. In addition, the tear strength of ELASTOSIL® LR 5040 products processed without postcuring exceeds that of postcured standard LSR grades. As a result, they can withstand mechanical stresses which may repeatedly occur in the usage of medical devices.
The ELASTOSIL® LR 5040 product line was recently complemented with a new grade and now covers the hardness range from 20 to 70 Shore A. In its cured state, the actual hardness of the non-postcured silicone elastomer deviates from the midpoint of the specification range by no more than three points. The product line can therefore be readily injection molded. Eliminating postcuring of silicone rubber components also creates significant streamlining and automation potential in the manufacturing process, particularly if located in a cleanroom environment, and facilitates rapid, efficient and cost-effective large-scale production.
Silicone Rubber Grades from WACKER
Source: WACKER