公开(公告)号：US06538064B2

公开(公告)日：2003-03-25

申请号：US09874301

申请日：2001-06-06

申请人： Takaharu Kawahara ,  Toshio Tuboi ,  Tetsuya Hikasa ,  Naoyuki Himi

发明人： Takaharu Kawahara ,  Toshio Tuboi ,  Tetsuya Hikasa ,  Naoyuki Himi

IPC分类号： C08F800

CPC分类号： C08J3/2053 ,  C08J2323/08 ,  C08K3/38 ,  C08L23/08

摘要： In the present invention, particles of an ethylene-vinyl alcohol copolymer (EVOH) are contacted with a solution containing a boron compound, whereby to obtain a substantially homogeneous distribution of the boron compound within the particles. For example, EVOH and the solution are continuously fed into a treatment apparatus and brought into contact with each other in the treatment apparatus, and the EVOH when continuously removed from the apparatus is in contact with the solution containing the boron compound in a concentration of at least 0.7 times but not more than 1.3 times a solution equilibrium concentration.

公开(公告)号：US06838517B2

公开(公告)日：2005-01-04

申请号：US09892543

申请日：2001-06-28

申请人： Takaharu Kawahara ,  Tetsuya Hikasa

发明人： Takaharu Kawahara ,  Tetsuya Hikasa

IPC分类号： C08F6/10 ,  C08F6/00 ,  C08F8/12 ,  C08F210/02 ,  C08F216/06 ,  C08F218/08 ,  C08F16/06

CPC分类号： C08F218/08 ,  C08F6/003 ,  C08F8/12 ,  C08F2800/20 ,  C08F210/02

摘要： The present invention provides methods for producing an ethylene-vinyl acetate copolymer and a saponified product thereof that can inhibit visible imperfections (particularly discoloration) at the time of molding by improving the process for recovering vinyl acetate. When the alcohol-based solvent to be blown in when recovering vinyl acetate is deoxidized so that its oxygen concentration becomes not more than 60 ppm, discoloration of a molded product of the above saponified product due to oxygen can be inhibited.

公开(公告)号：US06800687B2

公开(公告)日：2004-10-05

申请号：US10221725

申请日：2002-09-16

申请人： Takaharu Kawahara ,  Yukihiro Ohara ,  Toshio Tuboi ,  Tetsuya Hikasa

发明人： Takaharu Kawahara ,  Yukihiro Ohara ,  Toshio Tuboi ,  Tetsuya Hikasa

IPC分类号： C08F800

CPC分类号： B29C47/92 ,  B29C47/0004 ,  B29C47/38 ,  B29C47/805 ,  B29C2947/92704 ,  C08F8/12 ,  C08F2800/10 ,  C08F218/08 ,  C08F210/02

摘要： A method for producing a saponified ethylene-vinyl acetate copolymer (EVOH) comprises: supplying into a second reactor a solution containing the copolymer that is saponified partially with an alkali catalyst under a predetermined pressure in a first reactor; and saponifying further the partially-saponified copolymer in the second reactor under a pressure higher than the predetermined pressure in the first reactor. According to the method, an EVOH having a high saponification degree can be produced efficiently with a small amount of alkali catalyst.

摘要翻译： 乙烯 - 乙酸乙烯酯共聚物（EVOH）的制备方法包括：向第二反应器中加入含有在第一反应器中以预定压力部分地用碱催化剂皂化的共聚物的溶液; 并且在第一反应器中在高于预定压力的压力下进一步皂化第二反应器中的部分皂化的共聚物。 根据该方法，可以用少量的碱催化剂有效地制备皂化度高的EVOH。