US 12,479,987 B2
Ethylene vinyl ester based copolymer saponified pellets and film containing the same
Chih Chieh Liang, Taipei (TW); and Shih Yuan Su, Taipei (TW)
Assigned to CHANG CHUN PETROCHEMICAL CO., LTD., Taipei (TW)
Filed by CHANG CHUN PETROCHEMICAL CO., LTD., Taipei (TW)
Filed on Oct. 7, 2021, as Appl. No. 17/496,443.
Claims priority of application No. 202110513512.8 (CN), filed on May 11, 2021; and application No. 110116886 (TW), filed on May 11, 2021.
Prior Publication US 2022/0372261 A1, Nov. 24, 2022
Int. Cl. C08L 23/0861 (2025.01); C08F 2/44 (2006.01); C08F 18/08 (2006.01); C08F 218/08 (2006.01); C08F 218/12 (2006.01); B29C 48/00 (2019.01); B29C 48/08 (2019.01); B29C 48/285 (2019.01); B29K 23/00 (2006.01)
CPC C08L 23/0861 (2013.01) [C08F 2/44 (2013.01); C08F 18/08 (2013.01); C08F 218/08 (2013.01); C08F 218/12 (2013.01); B29C 48/022 (2019.02); B29C 48/08 (2019.02); B29C 48/288 (2019.02); B29K 2023/083 (2013.01)] 11 Claims
 
1. Saponified pellets of an ethylene-vinyl ester based copolymer having an ethylene content of 24-48 mole %, when the ethylene content is 24-35 mole %, a turbidity of the pellets as dissolved in a 60 wt % methanol aqueous solution is less than 300 NTU; or when the ethylene content is 36-48 mole %, a turbidity of the pellets as dissolved in an 80 wt % methanol aqueous solution is less than 200 NTU,
wherein the measurement method of the turbidity of the pellets dissolved in the 60 wt % methanol aqueous solution or in the 80 wt % methanol aqueous solution is to weight the pellets of 2.5 grams (g) and place the pellets into a 250 ml conical flask, and a 60 wt % or 80 wt % methanol aqueous solution of 84 g is added to the 250 ml conical flask, and the solvent and the pellets are heated under reflux in the conical flask for 2 hours until dissolving with the temperature of a hot plate is 450° C., and after that, the hot plate is cooled down to 60° C., and the solution turbidity is then determined using a Turbidimeter HI98703 instrument in accordance with ISO-7027 method.