微晶纤维素的羧甲基化反应

纤维素通过特殊的化学物理手段处理后，得到的微晶纤维素在有机溶剂中能很好地分散开，且所需要的有机溶剂的量较少。对其反应条件的探索表明，用微晶纤维素来进行羧甲基化反应，碱化和醚化时间较短，且一氯醋酸的利用率较高；用异丙醇作溶剂比乙醇作溶剂反应效果好。产物用1H－NMR研究表明，取代基在2位、3位和6位上的分布较均匀。     

皂角种子胶羧甲基化反应的研究与应用

研究了皂角种子胶与氯乙酸的羧甲基化反应,主要讨论了原料用量,原料颗粒大小及反应温度等因素对羧甲基化反应取代度的影响。     

酶解和羧甲基化对淀粉微球性能和形态的影响

通过酶解和羧甲基化对不同淀粉微球进行改性。借助于红外光谱、扫描电子显微镜、取代度测定以及吸水率测定对改性后的产物进行了表征。结果表明:淀粉的酶解和羧甲基化有利于提高微球的吸水率,但酶解时间过长反而会导致吸水率明显降低。     

交联氧化羧甲基化改性淀粉制备工艺研究

采用交联、氧化、羧甲基化多重淀粉改性技术,制备了具有羧甲基、交联、氧化淀粉的交联氧化羧甲基化改性淀粉。研究了乙醇、碱液(氢氧化钠溶液)、氯乙酸用量、反应温度和反应时间对取代度的影响,探讨了交联剂和双氧水用量对黏度及黏合力的影响,通过单因素实验得到了最佳工艺参数,解决了普通改性淀粉抗剪切稳定性差、不耐酸和盐、溶胀性差、透明度低等问题。     

福建毛竹制备羧甲基纤维素及其结构和性能表征

以福建毛竹为原料,经过四次加碱法制备羧甲基纤维素（CMC）,并通过FTIR、XRD、TGA、SEM手段对原料与产品的结构和性能进行表征。结果表明,制备CMC的最佳工艺条件为：精制毛竹5g,氢氧化钠6g,氯乙酸6g,乙醇质量分数为85％,第一次碱化温度为30℃,时间为90min,氢氧化钠加入量为总质量的80％;后三次碱化是在醚化过程中平均加入剩余20％的碱,醚化最终温度为70℃,醚化总时间为3h。在此工艺条件下,所得到的CMC的取代度为0．9137,黏度为37mPa·s。     

紫外光照射对淀粉羧甲基化反应的影响

探索了紫外光照射对淀粉羧甲基化反应的影响。紫外光照射可以提高淀粉的反应活性,提高反应速率,增加替代度。     

马铃薯淀粉渣的羧甲基化研究

研究了马铃薯淀粉渣与氯乙酸进行羧甲基化反应的一般规律，考察了反应温度、反应时间、原料配比等因素对产物取代度的影响，通过正交试验，找到了最佳反应条件，并对产物性能进行了测试。     

淀粉的羧甲基化研究

研究了不同原料配比 (淀粉、CH2 ClCOOH及NaOH的用量 )、反应介质以及反应时间等对淀粉羧甲基化反应的影响。结果表明 ,在其它条件不变时 ,( 1)当NaOH用量不大时 ,随着NaOH用量的增加 ,取代度 (DS)和CH2 ClCOOH的反应效率(RE)亦增加 ,当NaOH与CH2 ClCOOH的摩尔比为 2 .5∶1时 ,达到最大值 ,其后随着NaOH的增加 ,DS和RE急剧下降 ;( 2 )随着CH2 ClCOOH用量的增加 ,DS和RE增加 ,其中DS在CH2 ClCOOH与淀粉中葡萄糖基的摩尔比增大到 1∶1时达到最大值 ,而RE在CH2 ClCOOH与淀粉中葡萄糖基的摩尔比为 0 .75∶1时达到最高 ;异丙醇作为反应介质优于乙醇 ;在本实验的时间范围内 ,DS随着反应时间的增长而增大     

壳聚糖羧甲基化改性的制备研究

本文对壳聚糖进行了羧甲基化水溶性改性,获得较好效果,并对制备中的多种影响因素进行了分析讨论,提出了改性制备的较好条件。     

Experimental study on carboxymethylation of cellulose extracted from Posidonia oceanica

The production of carboxymethylcellulose (CMC) from bleached cellulose pulps obtained from Posidonia oceanica was explored. The optimal reaction conditions were studied for the carboxymethylation of cellulose in organic liquids. The carboxymethylation reaction was carried out with NaOH and monochloroacetic acid (MAC) as the reagent. Different alcohols were compared in terms of the degree of substitution (DS). The highest DS was obtained with n‐butanol. For this alcohol, the effects of the temperature, alkali concentration, and MAC concentration were studied. The reaction was also carried out in three consecutive steps. The resulting CMC had a DS of about 2.75. The functionalization of cellulose was checked using FTIR spectroscopy and ¹³C‐NMR. The X‐ray analysis showed that the crystalline structure of cellulose decreased when the DS increased and the structure was totally amorphous in high DS material. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1808–1816, 2006     

毛竹笋壳制备羧甲基纤维素

以废弃毛竹笋壳为原料,经过4次加碱法制备出了羧甲基纤维素,并通过FTIR、XRD、TGA、SEM手段对原料与产品进行了表征。实验结果表明,制备羧甲基纤维素的最佳工艺条件为精制竹笋壳5 g,氢氧化钠5 g,氯乙酸6 g,85%乙醇溶液为溶剂,第1次碱化温度和时间分别为30 ℃和90 min,加入氢氧化钠总质量的80%,后3次碱化是在醚化过程中平均加入剩余20%的碱,醚化最终温度为70 ℃,醚化总时间为3 h。在此工艺条件下,所得到的羧甲基纤维素的取代度为0.9341,黏度为35 mPa?s。     

不同配比碱金属化合物对焦炭反应性的影响

通过将一定粒度焦炭浸入不同配比碱金属化合物（K2CO3＋Na2CO3）溶液的方法在实验室制得焦样,用热重天平对焦样进行了焦炭反应性实验及SEM扫描电镜和能谱分析。研究结果表明,不同配比碱金属K、Na复合催化剂催化效果不同,K2CO3对焦炭溶损反应的催化作用贡献较大,焦炭溶损反应主要催化作用时间为前10min,浸碱焦炭试样中K、Na含量随碱溶液中K、Na含量增加而增加。     

Novel application of partial carboxymethylation in the wet processing of linen fabric

Scoured linen fabrics were treated with NaOH at different concentrations (1–7N). Unscoured (gray) linen fabrics were modified via partial carboxymethylation under different conditions, including monochloroacetic acid concentration (1–4N), sodium hydroxide concentration (0.5–3.5N), reaction time (30–180 min), and reaction temperature (30–90°C). Alkali treated and partially carboxymethylated linen fabrics were bleached using H₂O₂ (20 g/L), sodium silicate (3 g/L), and nonionic wetting agent (1 g/L) at pH 10 for 150 min at 95°C. The unbleached and bleached linen fabrics (alkali treated and partially carboxymethylated) were assessed for technical properties, namely, whiteness index (W.I.), loss in fabric weight, copper number, carboxyl content, and H₂O₂ decomposition percent. A comparison was made between the properties of the two substrates. It indicates that the properties of partially carboxymethylated linen fabric were comparable, if not superior, to alkali treated linen fabric. Hence it is advantageous to introduce partial carboxymethylation in the wet processing of linen fabrics since scouring and alkali treatment can be omitted. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 996–1001, 2007     

入侵植物加拿大一枝黄花制备二醋酸纤维素研究

利用加拿大一枝黄花(Solidago Canadensis L.)茎干为原料,提取高纯度α-纤维素浆粕,制备二醋酸纤维素(CDA),并对其制备工艺进行优化。结果表明,制备醋酸纤维素的工艺最优条件为:活化最佳液固比:1∶7,醋化过程催化剂最佳用量为9%～11%,醋酸酐用量为550%,醋化时间2 h,温度为50℃,皂化过程醋酸最佳浓度为70%,皂化最佳温度80℃,时间2 h。红外和X射线分析表明,加拿大一枝黄花纤维素的羟基被部分醋酸酯化,经过醋化和皂化后结晶度下降为29.88%。     

Effect of hydroxyl group content in ethyl cellulose on permeability in free films and coated membranes

The change in the water permeability, glass transition temperatures, and mechanical properties of ethyl cellulose with different degrees of substitution are presented. Studies of the hydroxyl group content on the polymer chains indicate that the mechanical properties of a free film decrease as the hydroxyl group content increases. This is thought to be due to the lower solubility of ethyl cellulose with a lower degree of substitution, as determined by the interaction constant in ethanol and the ability of the film with a high hydroxyl group content to hold more water. Furthermore, an increase in hydroxyl group content increases water permeability. Finally, a study of spray‐coated pellets has been performed and reveals a similar effect. The higher the hydroxyl group content, the higher the release rate and, at the same time, the decrease in Vickers hardness. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 529–535, 1999     

碱金属茚和芴衍生物的制备

在四氢呋喃（ＴＨＦ）、１，２－二甲氧基乙烷（ＤＭＥ）和二氧六环（Ｄｉｏｘａｎｅ）中，碱金属锂、钠、钾分别与茚（ＨＩｎ）和芴（ＨＦＩ）反应生成具有ＭＩｎ、ＭＦＩ型的茚基和芴基衍生物（Ｍ＝Ｌｉ，Ｎａ，Ｋ）。反应受溶剂的影响，反应活性次序为ＤＭＥ＞ＴＨＦ＞Ｄｉｏｘａｎｅ。对于不同的碱金属，则Ｋ＞Ｌｉ≥Ｎａ。茚钾和芴钾试剂可方便地用于过渡金属和稀土金属茚基、芴基衍生物的合成。     

Mechanisms of the alkali metal catalysed gasification of carbon

The catalytic effects of alkali metal salts in the gasification of carbonaceous materials by oxygen, steam and carbon dioxide are described. The most effective catalysts are generally the carbonates, oxides and hydroxides; other active salts tend to convert to these species under gasification conditions. Current theories of the mechanism of this type of catalysis are reviewed. Thermodynamic considerations, the results of thermal analysis and the magnitude of kinetic isotope effects suggest that cyclic sequences of elementary reactions are responsible for the catalytic phenomena.