Rubber Journal Asia Medical silicones
Silicones big ticket to health sector Long associated with feeding bottle nipples and
Healthy Asian market ust how big the silicone industry has become can be gleaned from a recent global silicone market report by Freedonia Group. It points to the Asia Pacific region as the largest and fastest-growing outlet for silicones through 2015 that also accounts largely for the 6.2% growth for silicones in various industries including healthcare. Moreover, the unique properties of silicones, such as thermal stability, good electrical insulation, high gas permeability, low chemical reactivity, non-stick and water repellent factors, are being sought after in several types of industries; notwithstanding the biofriendly nature of the polymer that makes it a viable option in healthcare. Freedonia pegs the industry’s worth at US$12.4 billion by 2015, citing also that the growing silicone market in China factors in the double-digit gains despite a slowing from the nearly 20% growth marked during the 2000-2010 period. The economic recession, particularly in North America and Western Europe, the historical centres of the world silicone industry, as Freedonia says, has slackened demand. But this will be balanced out by the incremental demands in Asian countries such as South Korea, Taiwan, India and Japan and an above-average growth in Central and South America, Eastern Europe and the Africa/Middle-East region, the report also indicates. Overall, the increased demand for silicone has undergone some baptism of fire. Today’s consumer standards have raised the bar for the silicone industry that it has to keep at stringent materials and environmental regulations as well as standards for biocompatibility, high performance and bacterial resistance.
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breast implants, silicone rubber is forecast to be the next billion dollar industry to tap the changing yet highly lucrative prospects in the medical and healthcare sectors, says Angelica Buan in this article.
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steady pipeline of innovative materials is becoming a prescription for big-ticket health and lifestyle industry and its medical and healthcare sectors. Thanks to the discovery of pathogens and improved management of emerging diseases that call for technical innovations in materials, the healthcare sector is expanding deep and wide. Alongside this, the silicones industry is filling in created niches by broadening its scope of application as well as improving properties. The basic raw material for silicone rubber is sand or silicon dioxide (silica). Sand is processed into pure silicone metal and then is reacted with methyl chloride, followed by an additional series of steps to create the many forms of silicone, from fluids and polymers to finished rubber bases and compounds. Unlike most plastics, silicones have a backbone of alternating atoms of silicon and carbon, with organic side chains that impart curability and other properties. One such form is liquid silicone rubber (LSR) that has some processing characteristics in common with thermoplastics, along with some notable differences that are inherent in a thermoset. LSR, thus, offers properties not obtainable with today’s TPEs. LSR’s are crosslinked utilising a platinumcatalysed reaction that produces no by-products. Once cured, LSR cannot be reshaped or easily reused or recycled. To do so requires a great deal of energy to overcome and break apart the crosslinks and/or the backbone itself. This same molecular structure makes LSR useful over a wide range of temperatures. At the same time, the strong bonds between the silicon and oxygen atoms mean that the polymer does not degrade until heated to temperatures above those that most other polymers can withstand. Another of LSR’s major attributes is its chemical inertness or purity. Coupled with its ability to withstand sterilisation processes, this makes LSR’s ideal for many medical and baby care products.
An alternative to latex ilicone products for medical and healthcare use vary and include, but are not limited to, tubes, drains, feeding tubes catheters and implants for long and short term use. Exhibiting a unique blend of characteristics including excellent biocompatibility with human tissue, silicones enable medical devices to be used comfortably and without producing an allergic or negative body reaction, compared to the use of natural rubber latex. A recent example of the use of silicone use instead of latex comes from US-based medical products maker MedPlast that has devised an assembly for a silicone pessary balloon used in a variety of female gynecological conditions, including prolapse. In years past, such devices were made of latex, which
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9 MARCH 2012
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