Multiple Molding Applications for Polyester Resin
Polyester resin is utilized in many different applications around the world. Chem-Trend has extensive experience working with polyester resins in our involvement in developing mold releases and related processing chemicals for both the composites and polyurethane molding industries.
Polyurethane molding utilizing polyester resin is most frequently seen in the manufacturing of shoe soles. Polyurethane systems for footwear soling can be based on either polyester or polyether polyols. These two system types have individually unique performance characteristics, and system selection is determined by end use of the shoe sole product.
Polyester resin is also utilized in the molding of a wide variety of composites for applications in transportation, energy, and sporting goods to name just a few. The selection of polyester resins for specific composite manufacturing applications is based upon the end requirements of the molded piece and the process being utilized to perform the molding operation.
Polyurethane Molding Applications for Polyester Resin
Polyester systems are generally fast to react, due to the fact that they are solid at room temperature and must be heated prior to use. The need for elevated temperatures to maintain a liquid form can make handling of polyester polyols difficult. Since the foam system is heated, mold temperature and cure times are generally reduced. Soles made with polyester polyols are less durable and can be susceptible to biological (bacteria/fungi) attack. These attributes are best suited to footwear markets with rapidly changing designs, or where consumers frequently purchase newer styles in order to keep up with current fashion trends. It should be pointed out that polyester systems are less expensive than polyether systems.
Chem-Trend has developed a global portfolio of products to meet the needs of shoe sole production applications. We supply to the largest and smallest customers around the world. With our global network of sales personnel and distributors, we are certain to have a product available – whatever your size or process. We can custom formulate water- or solvent-based products to meet your requirements for release ease and surface finish – our products can be tailored to meet a range of surface finishes from high to low gloss and everything in between. We are used to working with lists of "forbidden" chemical substances. We are able to supply tin-free release agents for almost all applications. (In the footwear industry it is generally known that no amount of tin will be tolerated.)
With over 50 years of experience in developing and manufacturing mold release agents and products for the polyurethane industry, Chem-Trend knows how to develop the right release products for your application. We also have a line of support products such as mold cleaners, mold preparation pastes and flush solvents to complement our release agents. Learn more about how we can help your shoe soling process.
Composite Molding Applications for Polyester Resin
Within the composite molding industry there are many different resins that may be utilized. Typically, but not exclusively, polyester, vinyl ester, epoxy, phenolic, polyether and DCPD resins are used by fabricators in the manufacture of composite parts. The selection of choice of one resin type over another is based upon the environment in which the fabricated composite component will spend its working life, and the physical characteristics required for the end part. The specific physical and mechanical properties of the resins are key parameters in the selection process.
The selection of a specific type of resin has a strong influence of the properties of the mold release agent/release system. In molding these resins the number of releases that will be obtained between applications of semi-permanent release agent touch-up coats will vary from resin to resin. Taking the extremes, it is highly likely that the maximum number of releases will be obtained in molding a polyester article, whereas substantially fewer releases would be expected when molding a product manufactured from phenolic-based resin.
Aside from just the effect on release ease, and time between release agent touch up, the resin selected may also influence other release system parameters which in-turn may affect end part quality, operational efficiency and mold life. Chem-Trend has over two decades of experience helping composite molders understand the interactions between molding process, raw materials being molded, part shape/weight, mold type and environmental factors to select the optimum release system for the task at hand. Learn more about how our experience in the field may be of benefit to your composite molding application.