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    Manufacturing method for cellulose ether having high degree of substitution
    22.
    发明授权
    Manufacturing method for cellulose ether having high degree of substitution 失效
    具有高取代度的纤维素醚的制造方法

    公开(公告)号：US4582899A

    公开(公告)日：1986-04-15

    申请号：US720927

    申请日：1985-04-08

    Applicant: Hiroyuki Nakamura

    Inventor： Hiroyuki Nakamura

    IPC: C08B11/04 ,  C08B11/187 ,  C08B13/00 ,  C08B11/00 ,  C08B11/16 ,  C08B11/18

    CPC classification number: C08B11/04 ,  C08B11/187 ,  C08B13/00

    Abstract: A manufacturing method for cellulose ether having a high degree of substitution characterized in that an etherifying agent represented by a general formula RCH.sub.2 X (where R is aromatic group, heterocyclic group, vinyl group or ethynyl group or the same group substituted and X is chlorine or bromine) is reacted with a uniform solution of cellulose acetate having a degree of substitution of 2.0 and over in an organic solvent in the presence of a base to manufacture a highly substituted cellulose ether having a degree of substitution of 2.0 and over per anhydrous glucose unit by a one stage reaction at a good yield.As a general method for manufacturing cellulose ether, a method for reacting an etherifying agent with alkali cellulose is now in use. For the general method, several improved methods have been proposed. However, it is difficult to manufacture cellulose ether having a degree of substitution of 2.5 and over by a one stage reaction using the general method. As manufacturing methods for cellulose ether other than the general method, a method for using a solvent-soluble cellulose derivative as the raw material and a method for using a special solvent in which cellulose is soluble were proposed. However, the former had a defect of a low yield and the latter had a defect of too long a reaction time.

    Abstract translation: 具有高取代度的纤维素醚的制造方法，其特征在于，由通式RCH2X（其中R是芳族基，杂环基，乙烯基或乙炔基或与之相同基团取代的醚化剂）和X是氯或溴 ）与有机溶剂中的取代基为2.0以上的醋酸纤维素的均匀溶液在碱的存在下反应，以通过以下方式制备高度取代的取代度为2.0的纤维素醚 一个阶段的反应以良好的收益率。 作为制造纤维素醚的一般方法，现在使用醚化剂与碱纤维素反应的方法。 对于一般方法，已经提出了几种改进的方法。 然而，通过一般方法，难以通过一步反应制造取代度为2.5以上的纤维素醚。 作为除一般方法以外的纤维素醚的制造方法，提出了使用溶剂可溶性纤维素衍生物作为原料的方法和使用其中可溶解纤维素的特殊溶剂的方法。 然而，前者具有低产量的缺点，后者具有反应时间太长的缺点。

    Methods for preparing alkali cellulose and cellulose ether
    29.
    发明授权
    Methods for preparing alkali cellulose and cellulose ether 有权

    公开(公告)号：US09617350B2

    公开(公告)日：2017-04-11

    申请号：US11614587

    申请日：2006-12-21

    Applicant: Mitsuo Narita ,  Masaki Tabata ,  Atsushi Yoshida ,  Hiroshi Umezawa

    Inventor： Mitsuo Narita ,  Masaki Tabata ,  Atsushi Yoshida ,  Hiroshi Umezawa

    IPC: C07H1/00 ,  C08B11/00 ,  C08B1/08 ,  C08B1/10 ,  C08B11/16 ,  C08B11/193

    CPC classification number: C08B1/08 ,  C08B1/10 ,  C08B11/00 ,  C08B11/16 ,  C08B11/193

    Abstract: The invention is a method for efficiently preparing alkali cellulose having a uniform alkali distribution therein. More specifically, the invention is a method for preparing alkali cellulose comprising steps of bringing pulp into continuous contact with an alkali metal hydroxide solution in a bucket conveyor type contactor to generate a contact mixture, and draining the contact mixture; a method for preparing a cellulose ether comprising use of the alkali cellulose thus prepared; and an apparatus for preparing alkali cellulose comprising a bucket conveyor contactor comprising at least one inlet port for introducing pulp and an alkali metal hydroxide solution at one end and at least one outlet port for discharging a contact mixture wherein the pulp and the alkali metal hydroxide solution can be moved from one end to the other end while bringing them into contact with each other to generate the contact mixture; and a drainer for separating a cake from the contact mixture discharged from the outlet port.

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