The thermal stability of silicone polymers, fluids and resins has been well documented and studied extensively. The high temperature performance of silicone adhesives and sealants used for electronics applications has only moderately been investigated. This report documents the effects of very high temperature exposures to electronics-grade silicone adhesives and sealants for such properties as...

Polymers are a broad class of materials which are made from repeating units of smaller molecules called monomers. Polymers can be natural in origin, such as the lignin of tree branches, the starches of homemade bread, or the chitin of lobster shells. Other polymers are called synthetic, because they are made by humans from naturally-occurring materials. Examples include polyesters used in cloth...

A study was conducted to examine the physical, mechanical, and chemical properties of composite (silicone/silica) breast implants as a function of implantation time. In the study the properties of SILASTCII gel-filled explants with in vivo duration times ranging from 4 months to 10 years were compared to lot-matched control (unimplanted) samples. Tensile strength properties were measured for bo...

with 'H nuclear magnetic resonance (NMR) technique using an internal control (5). Blood samples from animals given feed without siloxanes showed no signals originating from the silicones tested. In all blood samples from animals given feed with siloxanes, they were detected. In samples from animals given feed with PDMS, the mean concentration (± standard deviation) of siloxanes of 26 ± 14 pg/cm...

An array of in-line curvature sensors on a garment is used to monitor the thoracic and abdominal movements of a human during respiration. The results are used to obtain volumetric changes of the human torso in agreement with a spirometer used simultaneously at the mouth. The array of 40 in-line fiber Bragg gratings is used to produce 20 curvature sensors at different locations, each sensor cons...

BACKGROUND The mechanical interaction between blood vessels and medical devices can induce strains in these vessels. Measuring and understanding these strains is necessary to identify the causes of vascular complications. This study develops a method to measure the three-dimensional (3D) distribution of strain using tomographic particle image velocimetry (Tomo-PIV) and compares the measurement ...

Following silicone injection, end organ toxicity can occur. To our knowledge this report documents the first case of silicone embolization in the Caribbean and serves to highlight an emergent danger associated with its illicit use for cosmetic purposes in this region.

This study evaluated the effect of retentive areas on onlay preparations on the dimensional alterations in condensation and addition silicone materials. A standard model with an onlay preparation was made. Each impression material was used through the double or simultaneous impression technique (n=25), resulting in a hundred impressions of the same model. Impressions were poured with type IV de...

PURPOSE To observe the changes in permeability and elasticity in the cuff of the laryngeal mask airway (LMA) caused by repeated use. METHODS In vitro use was simulated on six # 4 LMAs on 140 occasions. Ambient air was insufflated into the cuff until a value of 200 mmHg intracuff pressure (ICP) was reached, and this was maintained for 50 min. After each simulation, the LMA was sterilized at 12...

The purpose of this study was to evaluate the Shore A hardness and surface roughness of two silicones for maxillofacial prosthetic treatment, under the influence of chemical disinfection and storage. Twenty-eight specimens were obtained, half of which were made of Silastic MDX 4-4210 silicone and, the other half were made of Silastic 732 RTV silicone. The specimens were divided into four groups...