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Ein anderes System nutzt Mitsubishi für eine neue Entwicklung:
Mitsubishi Heavy Industries have developed some very interesting technology with shape memory polymers based on polyurethanes. These materials are temperature sensitive, and modify both shape and hardness around a controllable glass transition temperature. This characteristic is being exploited in the making of garments that are comfortable and watertight, without a clammy feeling. The shape memory material fabric, DiAPLEX, which consists of an ultra-thin non-porous polymer membrane, is designed to react at a specific transition temperature. Upon reaching the transition temperature inside the garment (eg during strenuous physical activity, or external temperature changes), the membrane automatically becomes more waterproof or more permeable, as required. When the membrane is surrounded by sufficient heat, the material is activated to expand and becomes breathable in order to increase moisture and vapour permeability. Micro-Brownian motion, taking place at predetermined temperatures, allows the molecules in the membrane to form free space. At increasing temperatures, the molecular configuration changes, leading to the formation of free space, and enabling the transfer of heat and vapour from perspiration. When the temperature drops to below the transition temperature, the membrane remains closed in order to act as an insulator. The polymer molecular chains form a continuous surface, restricting the transfer of vapour and heat. In some ways, this membrane can be considered an advancement on membranes developed by the likes of Gore-Tex®, used in outdoor wear. This technology is used for clothing and sportswear, but is also being developed for medical applications, for example in intravenous cannula where the hollow tube has a Tg around body temperature and becomes soft and hence
more comfortable for the patient when in position. The material is also being suggested for use in sutures. Numerous potential
applications can be considered for such a material in catheters and valves, as well as potentially in wound care. Suggested applications also include stents, orthodontic support wires, arterial clips, handicap utensils, film for vegetable storage, self-creeprestoration protection covers for auto assembly lines, self-deployable spacecraft architecture, curly-straight doll hair, and anti-scald devices.
Quelle: http://www.diaplex.com/extremehp.html
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