Modified plastics are one of the largest sub-markets in the field of new materials—like modified PP, modified PA, PC/ABS alloys, flame-retardant ABS, glass fiber reinforced engineering plastics, etc. Each type has its specific testing needs. A complete modified plastics lab should cover four main types of testing: mechanical properties, thermal properties, processing performance, and flammability.

Mechanical properties are the "basic skills" in testing modified plastics. Universal testing machines are used to measure tensile strength, elongation at break, flexural strength, and flexural modulus (GB/T 1040, GB/T 9341). Impact testers are used for cantilever beam (Izod) and simply supported beam (Charpy) notched impact strength—these two indicators are crucial for evaluating toughening modifications. For glass fiber reinforced materials, the effect of fiber content on the anisotropy of mechanical properties also needs attention.

For thermal properties, DSC measures the melting point Tm, crystallization temperature Tc, glass transition temperature Tg, and crystallinity—these parameters directly reflect the heat resistance grade and processing window of the material. TGA is used to accurately measure glass fiber content, inorganic filler content like calcium carbonate, and thermal decomposition temperature. HDT/Vicat testers provide the maximum service temperature of the material.

Processing performance: Melt flow indexers (MFR/MVR) are daily must-tests in QC labs for modified plastics. Capillary rheometers can obtain viscosity data at high shear rates, useful for injection molding process simulation. Flammability: Horizontal/vertical burning testers (UL 94) and oxygen index testers evaluate flame retardancy.

Dehuisci (www.dehuisci.com) has been serving the modified plastics industry for 13 years, representing brands like Instron, TA, Mettler Toledo, and more. Phone: 0512-67071902.