Stereoregular poly(methyl(3,3,3-trifluoropropyl)-siloxane) polymers and
methods for making
    1.
    发明授权
    Stereoregular poly(methyl(3,3,3-trifluoropropyl)-siloxane) polymers and methods for making 失效
    立体定向聚(甲基(3,3,3-三氟丙基) - 硅氧烷)聚合物和制备方法

    公开(公告)号:US5401822A

    公开(公告)日:1995-03-28

    申请号:US190951

    申请日:1994-02-03

    摘要: The present invention is stereoregular poly{methyl(3,3,3-trifluoropropyl)siloxane} polymers and copolymers and methods for their making. The process involves reacting isomers of 1,3,5-trimethyl-1,3,5-tris(3',3',3'-trifluoropropyl)cyclotrisiloxane in the presence of an aprotic polar promoter and a lithium compound. The lithium compound initiates ring opening and polymerization of the isomers without effecting the steric arrangement of the isomers. Elastomers prepared by cross-linking polymers of the present invention can have sufficient cis 3,3,3-trifluoropropyl substitution to allow the elastomers to strain crystallize and provide reinforcement to the elastomers at typical use temperatures.

    摘要翻译: 本发明是立体配位聚{甲基(3,3,3-三氟丙基)硅氧烷}聚合物及共聚物及其制备方法。 该方法涉及在非质子极性促进剂和锂化合物的存在下使1,3,5-三甲基-1,3,5-三(3',3',3'-三氟丙基)环三硅氧烷的异构体反应。 锂化合物引发异构体的开环和聚合,而不影响异构体的空间排列。 通过本发明的交联聚合物制备的弹性体可以具有足够的顺式3,3,3-三氟丙基取代,以使弹性体在典型的使用温度下变形结晶并提供增强弹性体。

    Strain-crystallizing poly(methyl(3,3,3-trifluoropropyl)-siloxane)
elastomers and methods for making
    2.
    发明授权
    Strain-crystallizing poly(methyl(3,3,3-trifluoropropyl)-siloxane) elastomers and methods for making 失效
    应变结晶聚(甲基(3,3,3-三氟丙基) - 硅氧烷)弹性体和制备方法

    公开(公告)号:US5492993A

    公开(公告)日:1996-02-20

    申请号:US190953

    申请日:1994-02-03

    CPC分类号: C08G77/08 C08G77/24

    摘要: Strain-crystallizing poly{methyl(3,3,3-trifluoropropyl)siloxane} elastomers and methods for their making. The process comprises the cross-linking of cis stereoregular polymers prepared by reacting isomers of 1,3,5-trimethyl-1,3,5-tris(3',3',3'-trifluoropropyl)cyclotrisiloxane, where at least 30 percent of the isomers are of cis configuration, in the presence of an aprotic polar promoter and a lithium compound. The lithium compound initiates ring opening and polymerization of the isomers without affecting the steric arrangement of the leomars. Elastomers prepared by cross-linking these cis stereoregular polymers have sufficient cis 3,3,3-trifluoropropyl substitution to allow the elastomers to strain crystallize and provide reinforcement to the elastomers at typical use temperatures.

    摘要翻译: 应变结晶聚{甲基(3,3,3-三氟丙基)硅氧烷}弹性体及其制备方法。 该方法包括通过使1,3,5-三甲基-1,3,5-三(3',3',3'-三氟丙基)环三硅氧烷的异构体反应制备的顺式立构配体聚合物的交联,其中至少30% 的异构体是顺式构型,在非质子极性促进剂和锂化合物的存在下。 锂化合物引发异构体的开环和聚合,而不影响色谱柱的空间排列。 通过交联这些顺式立体规则聚合物制备的弹性体具有足够的顺式3,3,3-三氟丙基取代,以使弹性体在典型的使用温度下变形结晶并提供增强弹性体。

    Process for the manufacture of cellulose acetate
    5.
    发明授权
    Process for the manufacture of cellulose acetate 失效
    醋酸纤维素的制造方法

    公开(公告)号:US5608050A

    公开(公告)日:1997-03-04

    申请号:US573678

    申请日:1995-12-18

    CPC分类号: C08B3/06

    摘要: The specification discloses a process for the manufacture of cellulose acetate. The process reacts, at a temperature suitable for acetylation, an acetic acid activated pretreated cellulose raw material containing 100 parts cellulose by dry weight, and 0.5 to 40 parts of a bisulfate catalyst by dry weight of the cellulose. The bisulfate catalyst is selected from lithium bisulfate, sodium bisulfate, and potassium bisulfate. To enhance mixing with the activated and pretreated cellulose, the catalyst may be mixed with 2 to 4 parts of acetic anhydride by dry weight of the cellulose, and 4 to 6 parts of acetic acid by dry weight of the cellulose. In a further embodiment, 0.05 to 10 parts of a strong Bronsted acid by weight of the dry cellulose may be added as a co-catalyst.

    摘要翻译: 该说明书公开了一种制造乙酸纤维素的方法。 该方法在适于乙酰化的温度下,将干燥重量为100份纤维素的醋酸活化预处理纤维素原料和干燥纤维素0.5至40份硫酸氢盐催化剂反应。 硫酸氢盐催化剂选自硫酸氢锂,硫酸氢钠和硫酸氢钾。 为了增强与活化和预处理的纤维素的混合,催化剂可以通过纤维素的干重与2-4重量份的乙酸酐和干燥重量的纤维素的4至6份乙酸混合。 在另一个实施方案中,作为助催化剂可加入0.05至10份重量的干纤维素的强布朗斯台德酸。

    Radiation polymerizable starch ester-urethanes
    7.
    发明授权
    Radiation polymerizable starch ester-urethanes 失效
    辐射聚合淀粉酯

    公开(公告)号:US5138006A

    公开(公告)日:1992-08-11

    申请号:US652969

    申请日:1991-02-11

    CPC分类号: C08B31/00 C08F290/10

    摘要: Modified starch ester-urethanes prepared by reacting a starch ester containing residual hydroxyl groups with an ethylenically unsaturated isocyanate. The grafted starch ester is a urethane-containing product having pendent groups such as alphamethylstyrene and/or methacrylate moieties. The starch ester-urethane is capable of undergoing crosslinking reactions on exposure to ultraviolet radiation in the presence of a photoinitiator, and optionally ethylenically unsaturated monomers or oligomers. The ethylenically unsaturated starch ester-urethanes of this invention are useful for protective coatings for wood, metal, and plastics.

    摘要翻译: 通过使含有残余羟基的淀粉酯与烯属不饱和异氰酸酯反应制备的改性淀粉酯 - 聚氨酯。 接枝的淀粉酯是具有侧基的聚氨酯的产物,例如α-甲基苯乙烯和/或甲基丙烯酸酯部分。 淀粉酯 - 氨基甲酸酯能够在光引发剂和任选的烯键式不饱和单体或低聚物存在下暴露在紫外线辐射下进行交联反应。 本发明的烯属不饱和淀粉酯 - 聚氨酯可用于木材,金属和塑料的保护涂层。