The TPU performance introduced here includes three aspects: mechanical performance, physical performance, and environmental performance.
1. Mechanical properties:
The mechanical properties of TPU elastomer mainly include: hardness, tensile strength, compression performance, tear strength, resilience and wear resistance, and bending resistance. In addition to these properties, the mechanical properties of TPU elastomer also include high Shear strength and impact energy.
(a) Hardness: Hardness is an indicator of a material's ability to resist deformation, scratches, and scratches. The hardness of TPU is usually measured using Shore A and Shore D hardness testers, with Shore A used for softer TPUs and Shore D used for harder TPUs. The hardness is mainly determined by the hard segment content in the TPU structure, and the higher the hard segment content, the higher the hardness of the TPU. After the hardness increases, other properties of TPU will also change, with an increase in tensile modulus and tear strength, an increase in rigidity and compressive stress (load capacity), a decrease in elongation, an increase in density and dynamic heat generation, and an increase in environmental resistance. There is a certain relationship between the hardness of TPU and temperature. Cooling from room temperature to a sudden change in temperature (-4~-12 ℃), with no significant change in hardness; Under sudden temperature changes, the hardness of TPU suddenly increases and becomes very hard, losing elasticity, which is the result of the crystallization of soft segments.
(b) The relationship between hardness and constant elongation stress and elongation, as well as the relationship between hardness and tear strength. As the hardness of TPU increases, the 100% constant elongation stress and 300% constant elongation stress rapidly increase, and the elongation rate decreases. This is mainly due to the increase in hard segment content: high hard segment content makes it easier for the formed hard segment phase to form secondary crystals or crystalline structures, which increases the number of physical crosslinks and limits material deformation. If the material deforms, it is necessary to increase the stress, thereby increasing the constant elongation stress and decreasing the elongation rate. The relationship between TPU hardness and tear strength increases rapidly with the increase of hardness, and the reason for this is also the same as the explanation of modulus.
The formula and performance of TPU can be arranged and combined in a variety of ways. However, in practical formula design and industrial production, it is still very difficult to develop materials that can be truly used for high-end applications due to mutual limitations of raw materials (polyols, polyisocyanates, and chain extenders).
Oceanchem Group Limited (OCG) | OCG is sign of Oceanchem Group Limited
Flame retardant / polymer additives leading manufacturer in China.
With 30 years production experience of manufacture flame retardant and polymer additives with trade mark / brand GSAL/ Gsal. All flame retardant used widely and with good performance for: Polyamide(PA); polyester(PBT,PET); Polyolefin(PP,PE); Polystyrene (EPS/XPS- expanded or extruded polystyrene for insulation materials for construction); Polyurethane(PU); etc. also for industry: Plastics, Rubber , textile, construction , transportation, electronics and electrics devices , home appliances , paints and coatings, adhesives etc. many kind of flame retardant equivalent saytex8010/7010/3010/5010; FR720/PE-68/HP-800; SR130/ Emerald3000/FR122P; BT93W; PHT4; PHT4 diol/RB49/ RB79; BC52/BC58; BDP/CDP/TCPP/TPP/PX220/PX200 etc. comply with ISO/ESG/OHSAS/SGS etc SQM/ thirty party standard system.
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