Challenges in product development does not stop only at achieving functionalities that meet the needs of consumers but also extend to the development of production technology that answers the needs of manufacturers while remaining environmentally friendly.

   This is certainly true with the relation between the Chemicals Business, SCG, and COMOS. For over ten years, both parties have shared with each other techniques, work process, and customer needs in order to effectively co-develop innovations, one of which is the special-grade polyethylene known as SCG™ LLDPE S15 PU-stick series. Made possible through the collaboration between the two organizations, the material proves ideal for the exterior shell of coolers because it has higher adhesion strength to polyurethane compared to regular plastic resin, allowing it to bond with the layer of polyurethane foam better.

   All Around Plastics sat down with Mr. Sudjai Jirayapakorn, President of COMOS Corporation Company Limited, Thailand’s leading cooler manufacturer, and Mr. Lertsak Laosripaiboon, a technical service engineer and representative of the Chemicals Business, SCG, to recount the development of this high-efficiency special-grade plastic resin designed for coolers.

The Beginning of the Collaboration

   A former fisherman, Sudjai entered the cooler business during a shortage of coolers for storing fresh seafood. Using his knowledge of metalworking, he cast buckets from zinc, but as they were routinely used with saltwater, they were quickly corroded. This prompted him to look for alternative materials and eventually produce plastic coolers that is widely used today.

   “The key element that keeps the temperature in a cooler low is foam. Previously, only foam sheets were used. So, I developed spray foam that could be injected between the outer and inner plastic shells. To get the foam to adhere to the walls of the outer shells thoroughly and create insulation, it was necessary to blast the shells with abrasive material to create a rough surface. Our major problem was that the surface was not thoroughly roughened, especially in blind spots, which could result in peeling and denting. So, we tried to figure out a solution.”

   COMOS had its eyes set on international markets, but such a venture would involve compliance with green material requirements. That was where SCG stepped in. Volunteering as a mentor, SCG provided manufacturing techniques and knowledge and together, co-developed new plastic resin that not only reduced issues for COMOS but also had properties that would meet the needs of the global market.

   Lertsak recounted, “The beginning of this project was the cordial relationship between COMOS and us. They purchased products from us and consulted with us, while we regularly shared new technology with them. One day, COMOS told us that the injected foam kept peeling off. This problem was difficult to fix because the peeling occurred only in spots. And thus we embarked on a project to find a solution that would enable foam to adhere evenly across the surface of the shell.”

From Trust to Development

   In response to the issue, SCG had to formulate a new grade of plastic not available on the market. This led to the development of SCG™ LLDPE S15 PU-stick series. Outer shells of coolers produced with the new polyethylene resin could be readily injected with spray foam, allowing the manufacturer to skip the abrasive blasting process and avoid any issues relating to the process.

   “This plastic resin has three main advantages. First, it helps reduce waste in production, especially during abrasive blasting; in this process, plastic particles often fall to the floor and become dirty and difficult to recycle. This was one of COMOS’s requirements. Second, the resin makes it possible to entirely skip the abrasive blasting process, thus shortening the manufacturing process and prevent defects from uneven blasting. Both of these upsides lead to the last advantage, which is that it helps cut costs and reduce defective products that would otherwise be destroyed.”

   “In addition to developing a new product, another challenge was communicating to COMOS and making them understand that the smooth surface of the cooler produced from this resin could adhere to the foam just as before without the need of abrasive blasting and that the new cooler retained the same insulation efficiency and other functionalities,” added Lertsak.

Developing for a Better World

   While the new plastic resin changed the production method of coolers, the benefits extends beyond manufacturers. The resins also have a positive impact on the environment, and supports the concept of circular economy. With abrasive blasting no longer necessary, the manufacturing process consumes less raw material, creates less waste, and uses less energy, while the product emits less carbon dioxide per unit. This transition has helped reduce overall greenhouse gas emissions and could be one of the long term solution to global warming.

   Taking over 12 years from start to finish, the collaborative development of SCG™ LLDPE S15 PU-stick series has further strengthened the ties between COMOS and SCG.

   “COMOS and SCG are like brothers. Throughout our 30 years in business, we have a great customer-supplier relationship and regularly share knowledge with each other. Starting from just a few dozen tons, we now order hundreds of tons of raw material, all from SCG, which is recognized in the market for quality. Each lot of our products comes with a certificate guaranteeing its quality for both domestic and international customers. Our success today comes from the sincerity and understanding between the two companies. In the future, our company is venturing into the injection molding of large items, and we will continue to use SCG’s resin because we believe in the long-standing quality,” said Sudjai.

   Lertsak shared how impressed SCG was with COMOS. “The development of the plastic resin was a success because COMOS was open to experiment, adjust formulas, and mold the cooler multiple times. COMOS also gave us feedback from product users, which enabled us to address the needs of both the manufacturer and consumers comprehensively.”

   “Through this experience, we have found that when we work as a team with customers and provide our knowledge and expertise to help them, we can achieve mutual success.”

For more information on SCG™ LLDPE S15, please contact us at rotomolding@scg.com.