Method for recovering caprolactam
    114.
    发明专利
    Method for recovering caprolactam 失效
    恢复CAPROLACTAM的方法

    公开(公告)号:JPS5970662A

    公开(公告)日:1984-04-21

    申请号:JP17956882

    申请日:1982-10-12

    Applicant: Unitika Ltd

    Abstract: PURPOSE: To recover efficiently ε-caprolactam, by polymerizing an oligomer consisting essentially of a cyclic dimer of the ε-caprolactam in the presence of phosphoric acid under heating at a specific temperature, and carrying out the decomposition procedure thereof.
    CONSTITUTION: An oligomer consisting essentially of a cyclic dimer of ε-caprolactam is heated in the presence of 1W20wt% phosphoric acid catalyst within 280W320°C temperature range to convert 50wt% or more oligomer into polycaprolactam, which is then subjected to the decomposition procedure, e.g. vacuum distillation or steam distillation, etc. to distill away and recover the ε- caprolactam. Preferably, the oligomer is converted into the polycaprolactam, which is in particular preferably mixed with a melt of a recovered polymer formed in another system, e.g. waste yarns, and subjected to the decomposition procedure for easily adjusting the amount of the phosphoric acid.
    COPYRIGHT: (C)1984,JPO&Japio

    Abstract translation: 目的:通过在特定温度下加热下,在磷酸存在下聚合基本上由ε-己内酰胺的环状二聚体组成的低聚物,并进行其分解步骤,来有效地回收ε-己内酰胺。 构成:基本上由ε-己内酰胺的环状二聚体组成的低聚物在1-20重量%的磷酸催化剂存在下在280-320℃的温度范围内加热,以将50重量%或更多的低聚物转化成聚己内酰胺, 到分解过程,例如 真空蒸馏或蒸汽蒸馏等,以蒸馏除去并回收ε-己内酰胺。 优选地,将低聚物转化成聚己内酰胺,其特别优选与在另一系统中形成的回收聚合物的熔体,例如, 废纱,并进行分解处理以容易地调节磷酸的量。

    116.
    发明专利
    失效

    公开(公告)号:JPS5442992B2

    公开(公告)日:1979-12-17

    申请号:JP6624174

    申请日:1974-06-11

    118.
    发明专利
    失效

    公开(公告)号:JPS5320516B2

    公开(公告)日:1978-06-27

    申请号:JP1778573

    申请日:1973-02-12

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