Yuriy Sakunenko, deputy general director at Specplast-M Ltd. (Russia)
Report points Issues of cooling – unnecessary heat take-off – were and are actual for ensuring of optimal operating conditions for various technical devices (computers, motor drives, heating appliances, filament lamp, LED lamps). Generated heat usually is taken-off by heat conductivity (it is characterized with heat-conduction coefficient ? Wt/m·K) for some distance and then is passed (dissipated) to environment. Generally at so-called natural cooling (without ventilators) environment capability to take heat has certain limit. According to calculations and experimental data increase of heat-conduction coefficient up to more than 5-10 Wt/m·K is excess and does not result in increase of heat take-off. Thus for naturally cooled devices it is not necessary to use materials with heat conductivity greater than 5-10 Wt/m·K. Almost 50-fold gap between real (0.15 Wt/m·K) and required heat conductivity for production of cooling devices till recently has not allowed developers to apply recognized economic effect of plastics in mass technologies. Such sharp increase of heat conductivity became possible only now due to selection of special technological additives, usage of fillers with high heat conductivity (up to 150-250 Wt/m·K), specialized technological equipment for high and extra high loading. A range of polymer composites producers launched series production of some heat dissipating polymer composites product lines. Their heat conductivity varies from 1.0 to 40.0 Wt/m·K and in some cases is be highly competitive with stainless steel (?stainless steel= 18.0 Wt/m·K). At the same time such plastics weight as much as one fourth compared to steel. The most common application of heat dissipating polymer composites is production of so-called thermo interfaces – products ensuring heat transferring directly from heat generator to environment. Typical thermo interface is common cooling radiator. The products made of heat dissipating polymer composites are produced by injection molding at standard injection molding machines. It is principally important that heat dissipating polymer composites due to applied technology allow to easily manufacture products of almost any shape (3D design) with more complex developed effective heat conductive radiator surface as distinct from aluminum radiators. Along with thermo interfaces heat dissipating polymer composites find their application in other products (heat pipes, coils, plugs with wire wrap, single-use crystallizers, liquid-based heat exchengers, temperature sensors, heat-exchanging panels). Production of LED and LED lamps is probably the most prospective and capacious application for heat dissipating polymer composites. Some technologies using heat dissipating polymer composites as design base for direct allocation of light-emitting crystal and heat radiator. Lamps designers combine in one easily molded single housing made of heat dissipating polymer composites three functions at the same time: light gathering (beam deflector function), excess heat energy dissipation (radiator function) and finally material for housing (integrating environment function). The examples stated above reflect only a part of potential applications for heat dissipating polymer composites and prove expert opinion that heat dissipating polymer composites will be one of the most demanded polymer material in the near decade.