Chang Chun Petrochemical Co., Ltd.

Huan Ming Chang

Chih Chieh Liang

Weng Shing Lin

Wen Hsin Lin

Chia Hao Hsu

Jing Jin Tsai

Li Shing Lin

Chia Ying Chen

Kuang Hui Fan

Pellets of ethylene-vinyl alcohol copolymer having lamellar stacks of ethylene-vinyl alcohol copolymer with a long period determined by small-angle X-ray scattering of at least 8.35 nm. The lamellar stacks of ethylene-vinyl alcohol copolymer may have an average crystalline lamellar thickness of at least 6 nm. Additionally or alternatively, the lamellar stacks of ethylene-vinyl alcohol copolymer may have an average amorphous lamellar thickness of at least 2.35 nm. Methods are also provided for producing pellets of ethylene-vinyl alcohol copolymer, such as those having preferable lamellar stack properties, as described above.

Ethylene-vinyl alcohol copolymer and producing method thereof

Extruded films comprising ethylene vinyl alcohol copolymer (EVOH) with substantially no blow holes therein, are formed by using a pellet feed to the extruder wherein 90-100 wt. % of the pellets pass through an ASTM size 5 sieve and 0-10 wt. % of the pellets are finer than a number 10 mesh (ASTM Sieve size). Uniform feeding to and through the extruder with a lack of bridging of the EVOH pellet feed have been observed.

Ethylene vinyl alcohol copolymer pellet, method for extrusion of the pellet and extrusion molded film produced thereby

The present invention relates to a method for increasing the heat-resistant of ethylene-vinyl alcohol copolymer (EVOH), the method is characterized by using a mixture of acetic acid, magnesium dihydrogen phosphate, and potassium dihydrogen phosphate at a certain ratio as an acid-treating solution in the acid-treating procedure of a process for preparing EVOH. The EVOH produced by the method of the present invention exhibits an excellent heat-resistance and does not become yellowing attributed to the elevated processing temperature. Also, the EVOH generated by the method of the present invention exhibits a uniform heat-resistance since the additives are dispersed evenly in the EVOH.

Method for improved the handling heat-resistance of the ethylene-vinyl alcohol copolymer

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Taipei, Taiwan

Huan Ming Chang