Cyclic process for producing an alkali solution of cellulose carbamate
and precipitating the carbamate
    1.
    发明授权
    Cyclic process for producing an alkali solution of cellulose carbamate and precipitating the carbamate 失效
    制备氨基甲酸纤维素碱溶液并沉淀氨基甲酸酯的循环方法

    公开(公告)号:US4639515A

    公开(公告)日:1987-01-27

    申请号:US779798

    申请日:1985-09-24

    摘要: The present invention concerns a cyclic process for producing an alkali aqueous solution of cellulose carbamate, for precipitating the cellulose carbamate from the alkali solution and for recovering and recycling the remaining chemicals. The process comprises the following steps: (a) an alkali solution of cellulose carbamate is prepared by dissolving cellulose carbamate in an aqueous solution of sodium hydroxide, (b) the solution obtained in step (a) is contacted with a precipitation aqueous solution containing sodium carbonate, whereby the cellulose carbamate is precipitated and can be removed, (c) from the solution in step (b) sodium carbonate is crystallized and is returned to the precipitant solution in step (b), and (d) mother liquor containing sodium hydroxide, obtained, i.e. remaining from, step (c), is returned to step (a) for dissolving cellulose carbamate. The crystallizing in step (c) is accomplished in two or several steps by cooling.

    摘要翻译: 本发明涉及一种制备氨基甲酸纤维素的碱性水溶液的循环方法,用于使碱性溶液中的氨基甲酸纤维素沉淀并回收和循环剩余的化学物质。 该方法包括以下步骤:(a)通过将氨基甲酸纤维素溶解在氢氧化钠水溶液中制备氨基甲酸纤维素的碱溶液,(b)将步骤(a)中得到的溶液与含有钠的沉淀水溶液接触 碳酸盐,由此氨基甲酸纤维素被沉淀并可以除去,(c)从步骤(b)中的溶液中,碳酸钠结晶并在步骤(b)中返回沉淀剂溶液,和(d)含有氢氧化钠的母液 从步骤(c)获得的剩余物质返回步骤(a),以溶解纤维素氨基甲酸酯。 步骤(c)中的结晶通过冷却两个或几个步骤完成。

    Method of producing cellulose carbamate
    3.
    发明授权
    Method of producing cellulose carbamate 失效
    生产氨基甲酸纤维素的方法

    公开(公告)号:US4567255A

    公开(公告)日:1986-01-28

    申请号:US710689

    申请日:1985-03-12

    IPC分类号: C08B15/06

    CPC分类号: C08B15/06

    摘要: The invention is directed to a procedure for manufacturing cellulose carbamate by reacting isocyanic acid and cellulose at elevated temperature. In the procedure, cellulose, to which biuret or a mixture of biuret and urea has been admixed or absorbed, is heated at a temperature over 170.degree. C. for a sufficient time to produce a quantity of isocyanic acid sufficient for formation of the cellulose carbamate and for accomplishing the reaction between cellulose and isocyanic acid. The heating is accomplished at 170.degree.-250.degree. C., preferably at about 220.degree. C. The biuret quantity is 3-50% by weight of the cellulose weight and the urea quantity is 0-95% by weight of the cellulose weight.

    摘要翻译: 本发明涉及通过异氰酸和纤维素在升高的温度下反应制备纤维素氨基甲酸酯的方法。 在该方法中,已经将缩二脲或缩二脲和脲的混合物混合或吸收的纤维素在170℃以上的温度下加热足够的时间以产生足以形成氨基甲酸纤维素的量的异氰酸酯 并用于完成纤维素和异氰酸之间的反应。 加热在170°-250℃,优选约220℃下进行。缩二脲的量为纤维素重量的3-50重量%,尿素的量为纤维素重量的0-95重量%。

    Method of producing alkali-soluble cellulose derivative
    4.
    发明授权
    Method of producing alkali-soluble cellulose derivative 失效
    生产碱溶性纤维素衍生物的方法

    公开(公告)号:US4404369A

    公开(公告)日:1983-09-13

    申请号:US341133

    申请日:1982-01-20

    IPC分类号: C08B3/14 C08B15/06

    CPC分类号: C08B15/06

    摘要: An alkali-soluble cellulose derivative is produced by treating cellulose with liquid ammonia having urea dissolved therein, removing the ammonia, resulting in cellulose having urea distributed therethrough, and heating the thus obtained cellulose-urea to cause reaction between the urea and cellulose and form alkali-soluble cellulose carbamate. This cellulose carbamate can be precipitated from alkaline solution in the form of cellulose carbamate film or fiber.

    摘要翻译: 碱溶性纤维素衍生物是通过用溶解有尿素的液氨处理纤维素而生成的,除去氨,得到分布有尿素的纤维素,加热得到的纤维素 - 尿素,使尿素与纤维素反应形成碱 - 可溶性纤维素氨基甲酸酯。 这种氨基甲酸纤维素可以以氨基甲酸纤维素薄膜或纤维的形式从碱性溶液中沉淀出来。

    Procedure for producing soluble cellulose derivatives
    5.
    发明授权
    Procedure for producing soluble cellulose derivatives 失效
    生产可溶性纤维素衍生物的方法

    公开(公告)号:US4486585A

    公开(公告)日:1984-12-04

    申请号:US537379

    申请日:1983-08-30

    摘要: The present invention concerns a procedure for producing cellulose carbamate from cellulose and urea. To avoid alkali treatment of the cellulose used as starting material with a view to decreasing the degree of polymerization of the cellulose, the cellulose in web form is exposed to a radiation dose of preferably 0.5 to 10 Mrad from a radiation source, whereafter the cellulose is reacted with urea at elevated temperature.

    摘要翻译: PCT No.PCT / FI82 / 00069 Sec。 371日期1983年8月30日 102(e)日期1983年8月30日PCT申请日1982年12月30日PCT公布。 出版物WO83 / 02278 日期:1983年7月7日。本发明涉及从纤维素和尿素生产纤维素氨基甲酸酯的方法。 为了减少纤维素的碱处理以减少纤维素的聚合度,纤维素形式的纤维素从辐射源暴露于优选0.5-10Mrad的辐射剂量,之后纤维素是 在高温下与尿素反应。