| CPC C08J 9/122 (2013.01) [B29C 44/0484 (2013.01); B29C 44/3415 (2013.01); B29C 44/3419 (2013.01); B29C 44/3453 (2013.01); B29C 44/348 (2013.01); C08J 7/048 (2020.01); C08J 9/0023 (2013.01); C08J 9/0061 (2013.01); C08J 9/0066 (2013.01); B29C 44/022 (2013.01); B29C 44/0461 (2013.01); B29K 2021/003 (2013.01); C08J 7/0427 (2020.01); C08J 2201/032 (2013.01); C08J 2201/034 (2013.01); C08J 2201/036 (2013.01); C08J 2203/06 (2013.01); C08J 2203/08 (2013.01); C08J 2205/044 (2013.01); C08J 2205/052 (2013.01); C08J 2300/22 (2013.01); C08J 2300/26 (2013.01); C08J 2367/00 (2013.01); C08J 2375/04 (2013.01); C08J 2377/00 (2013.01); C08J 2429/04 (2013.01); Y10T 428/249976 (2015.04); Y10T 428/249977 (2015.04); Y10T 428/249978 (2015.04); Y10T 428/249979 (2015.04); Y10T 428/249987 (2015.04); Y10T 428/249991 (2015.04); Y10T 428/249993 (2015.04)] | 6 Claims |

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1. A semi-continuous preparation method of a thermoplastic elastomer (TPE) physically-foamed roll, comprising the following steps:
(1) sequentially drying and premixing a TPE and additives, and subjecting a resulting mixture to continuous extrusion with a twin-screw extruder, calendering, and winding to obtain a precursor TPE roll;
(2) impregnating the precursor TPE roll obtained in step (1) in a high-pressure fluid to obtain an impregnated TPE roll, and subjecting the impregnating TPE roll to a quick freezing and gas-locking treatment and low-temperature storage, wherein a mass content of the high-pressure fluid in the impregnated TPE roll is 1% to 15%; the quick freezing and gas-locking treatment is conducted at −20° C. to −100° C.; the low-temperature storage is conducted at −60° C. to −20° C.; and the high-pressure fluid for the impregnating comprises at least one selected from the group consisting of a CO2 fluid and a N2 fluid; and
(3) heating an impregnated TPE roll obtained after the low-temperature storage in a heating medium for physical foaming, and roll pressing, cooling, and winding a foamed material to obtain the TPE physically-foamed roll, wherein the heating medium is hot air or hot water;
wherein in step (1), the precursor TPE roll further comprises a gas blocking layer, and a preparation method of the precursor TPE roll comprises: sequentially drying and premixing the TPE and the additives, and subjecting a resulting mixture to continuous extrusion with a twin-screw extruder and calendering; and coating a surface of the elastomer with a PVA-containing aqueous solution, and drying and winding a resulting material to obtain the precursor TPE roll;
the gas blocking layer has a thickness of 0.01 mm to 0.05 mm; and a mass content of PVA in the PVA-containing aqueous solution is 5% to 30%;
in step (2), the high-pressure fluid for the impregnation has a pressure of 1 MPa to 7 MPa, and the impregnation is conducted for 1 h to 24 h.
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