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UL 94 Test Standards for PlasticsOne of the key criteria in determining the suitability of plastics, such as Innovative Polymers’ polyurethanes, for building appliances, electronics and under-the-hood vehicle components is the Underwriters' Laboratories (UL) flammability rating of the materials. UL has assigned 12 different flame classifications to materials based on the results of lab-scale flame tests. Moisture ContaminationPolyurethanes are moisture sensitive materials. Polymers that are exposed to moisture may form an in-dissolvable skin on the resin surface. Calculating ShrinkageBefore casting a polyurethane part, an accurate assessment of shrinkage is a key to obtaining dimensionally accurate results. Shrink in polyurethane systems, and other thermoset plastics, is affected by several factors. Air BubblesTrapped air in a mixed polyurethane resin system can produce bubbles in the surface or wall of a cast part. To prevent the formation of voids, care must be taken during the mixing process. Soft Spots / Incomplete CureThe most common cause of incomplete curing is the use of inaccurate resin to hardener ratios and inadequate mixing of system components.
Coloring Innovative Polymers Products
Innovative Polymers provides a color-matching service for customers who purchase our polyurethanes. However, before considering polyurethane pigmentation, there are many factors to consider. Painting Cured Polyurethane PartsMany modelmakers, prototypers and molders of polyurethane parts must paint cured plastic surfaces to attain a production-quality finish. Some customers avoid painting by color-matching the selected polyurethane to the desired shade. Innovative Polymers specializes in color matching our materials to virtually any Pantone color. However, for projects that require painted surfaces, the following procedures can help ensure high-quality results. |