JEC COMPOSITES MAGAZINE - Issue #38 - January/February 2008 - 41

FEATURE “Resins and Gelcoat” New generation resin systems for wind blade and high speed railway In the past, the generation of electricity by wind force was of interest to a few scientists and environmentalists only. In the 1970's, wind-generated electricity was as costly as it was impractical, and has continued to be so until recently. has excellent functional characteristics, such as low viscosity (200-300cps), adjustable gel time to satisfy the requirements of any manufacturing process, and lower exothermic temperature; it also combines well with glass fibre and reacts at room temperature without extra pressure. Properties of SW2511-1 vs. traditional epoxy system ROBERT TSAI, PRESIDENT Swancor IND. CO., LTD. T he soaring price of oil continues to push up the cost of electricity generation, and the environmental cost of pollution is also steadily increasing. As a result, vast resources have been allocated worldwide to develop alternative sources of power, including wind power, solar energy and hydro-electric generation. Wind power is now becoming a viable alternative to generate electricity. With the support of governments worldwide, the cost of wind-generated electricity is falling. At present, it costs less than coal-generated electricity, and the same as natural gas or oil. Properties Gel time (note 1) Exothermic peak temperature (note 1) Tensile modulus Tensile strength Flexural strength Flexural modulus SW2511-1 9-10hrs 35-40°C 3.5GPa 75-79MPa 130-135MPa 3.5-3.8GPa Traditional epoxy system 6-7hrs 50-70°C 2.8-3.2GPa 70-75MPa 125-130MPa 2.9-3.2GPa Testing standard See note 1 See note 1 ASTM D638 ASTM D638 ASTM D790 ASTM D790 Note 1: Measuring conditions: 100g at 23°C in air. New epoxy resin for optimized blades A critical component for wind-generated electricity is the wind blade. Optimizing the blade leads to higher powergenerating efficiency and lower costs. Although open moulding and wet lay-up are still used, longer blades (in excess of 37.5 m) now have two alternative modes of production. Vacuum-assisted resin transfer moulding (VARTM) and infusion are those two popular ways. As blade design has improved, epoxy resin systems are now commonly used. These resins harden at low temperature (reacting between 5~50°C) and have a low shrink rate (1~3%). They offer excellent adhesive, mechanical, insulating and corrosion-resistance properties, are stable (can be stored more than one year without hardener), and exhibit excellent mechanical strength. Generally speaking, epoxy resin performs well. However, in some cases, the resin viscosity is too high and the operating time too short to be suitable for the VARTM process. Therefore, these shortcomings must be corrected in order to improve quality and produce larger blades. Swancor has already developed a new generation epoxy resin system, SW2511-1, for VARTM production of wind blades. SW2511-1 The SW2511-1 system has earned GL 2000 (Germanischer Lloyd) certification for epoxy resins that meet wind-blade manufacturing requirements. More information Swancor is a professional manufacturer of specialty chemicals. Our products have been widely used for various industries such as petrochemical, power, electronic, marine and pulp, windmill… etc, by providing the superior composite material for the application of anti-corrosion and high mechanical properties. Based on the clear energy demand in the global market, Swancor has been participated into wind blade material for years, and we fully dedicated in developing the cutting-edge composite for the future. It completely appears the R&D capability and technology of Swancor has leaped into a new stage of “environmental protection” and “ energy saving” industry. No38 January - February 2008 / JEC Composites Magazine

JEC COMPOSITES MAGAZINE - Issue #38 - January/February 2008

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #38 - January/February 2008