Fats refer to vegetable oils and animal fats. As a material of TPU elastomer, its grease resistance is an important indicator of whether it can be used in food contact. The resistance of TPU to vegetable oils and animal fats is discussed here.

(1) The results of vegetable oil resistance show that, compared with the initial value, the hardness of the two TPUs increased or decreased after the PET-TPU soaked in vegetable oil. The Shore A hardness of 95 increased by 2%, and the Shore A hardness of 85 decreased by 4%; PVC and Nitrile rubber has increased, while neoprene and natural rubber have decreased by 57% and 100%, respectively. Compared with the initial value, the tensile strength of PET-TPU increased by 57%; PVC also increased, but nitrile rubber, chloroprene rubber and natural rubber dropped significantly after soaking in vegetable oil, to 55%, 89% and 99% respectively. It can be seen that TPU is quite resistant to vegetable oils.

(2) Resistance to animal fat” Table 10-80 shows the changes in hardness and tensile strength of PET-TPU immersed in animal fat at 70°C×42d, and compared with certain plastics and rubbers. The results showed that compared with the initial value, after PET-TPU soaked in animal fat, the Shore A hardness of 95 increased by 1%, and the Shore A hardness of 85 decreased by 7%; PVC and nitrile rubber also increased, while neoprene and natural rubber Rubber dropped by 70% and 100%, respectively. Compared with the initial value, the tensile strength of the two hardnesses of PET-TPU increased by 27% and 40%, respectively; PVC increased by 23%, while nitrile rubber, neoprene rubber and natural rubber decreased by 11%, 53%, and 99%. %. It can be seen that TPU resistance to animal fats is also quite good.