乙交酯

MATERIALS: Paclitaxel degradable material (PLLA:PGA=9:1) were offered by Changchun Applied Chemistry Institute of Chinese Academy of Science. Human umbilical arterial smooth muscle cells were purchased from Baster, Wuhan, China.

材料：紫杉醇可降解材料（左旋丙素酯与聚乙交酯的比例为9：1）由中国科学院长春应用化学研究所提供。

The affections on the yield of DLLA caused by catalyst, temperature and time etc. were studied. By using ethylene glycol as diluent, the distillate temperature of DLLA was lowed and the carbonization phenomenon could be avoided, which caused the yield of DLLA increasing from 36.8% to 51.3%. The molecular weight of PDLLA prepared by this method could reach 184,000. DLLA and PDLLA was characterized and analyzed by DSC, XRD and IR.The key of direct method to synthesize PDLLA is the exclusion of H2O from reaction system.

丙交酯开环聚合制备PDLLA的关键在于中间体D，L-丙交酯的制备，研究了催化剂、反应温度、反应时间等因素对DLLA产率的影响，通过在反应体系中加入稀释剂乙二醇，DLLA的馏出温度明显降低，避免了DLLA在蒸馏过程中产生碳化现象，并使DLLA的平均产率由36.8％提高至51.3％，制备的PDLLA分子量最大值达18.4万。

Objective To study the pH and temperature sensitive properties of sulfamerazine oligomers-polyε-caprolactone-co- DL -lactide-b-ethyleneglycol- b -ε-caprolactone-co-DL-lactide-sulfamerazine oligomers（OSM1-PCLA-PEG-PCLA-OSM1）block copolymer and evaluate sustained release effect of 5-fluorouracil release from the loaded hydrogel in vitro.

摘要目的为嵌段共聚物磺胺甲嘧啶低聚物-聚-ε-己内酯-丙交酯-聚乙二醇-聚-ε-己内酯-丙交酯-磺胺甲嘧啶低聚物（sulfamerazine oligomers-poly(ε-caprolactone-co- DL -lactide-b-ethyleneglycol- b-ε-caprolactone-co-DL-lactide)-sulfamerazine oligomers，OSM1-PCLA-PEG-PCLA-OSM1作为缓控释给药系统的载体提供依据。

The structure and properties of the resulted polymer were analysed by infrared spectroscopy and differential scanning calorimetry, etc.

采用红外IR，DSC等方法表征了聚乙交酯的结构和性质。

The poly grafted starch copolymer was synthesized by the reaction of glycolide and starch in dimethyl sulfoxide with triethylamine as catalyst.

摘要以乙交酯和淀粉为原料，三乙胺为催化剂，在二甲基亚砜介质中合成了聚羟基乙酸接枝淀粉共聚物。

Because, until now, we only knew how to make these biodegradable polymers using two monomers (the basic components of polymers), lactide and glycolide. It is rather like making a bead necklace when only green and red beads are aailable.

因为，直到现在，我们只知道如何利用这些生物可降解聚合物使用良种单层膜，脱水乳酸和乙交酯，它就像党只有绿色和红色珍珠时也可以制成项链。

Mechanism of poly(dioxanone- co -glycolide) sutures in vitro degradation was studied by DSC and X-ray diffraction and the surface morphology was studied with photography for the purpose of improving properties of absorbable sutures.

用DSC和X-ray衍射法对聚对二氧环己酮-乙交酯缝合线的初期体外降解过程进行了研究，并使用纤维摄影仪对纤维在降解过程中的表面形态变化进行了观察。

Then two star-shaped oligomers with designed molecular weights 5000 g mol-1 and 10000 g mol-1, respectively, were synthesized from D, L-lactide and glycolide as raw materials and pentaerythritol as initiator under catalysis of dibutyltin oxide.

以合成的丙交酯和乙交酯为原料，季戊四醇为引发剂，氧化二丁基锡为催化剂合成出设计分子量为5000和10000两种预聚物。

Linear and star-shaped hydroxy-terminated polys were synthesized by reacting L-lactide with co-initiators such as poly,hydroxyethyl methycrylate,trimethylolpropane,mannitol and sorbierite in the presence of stannous octoate as catalyst.

以辛酸亚锡为催化剂，分别以聚乙二醇、甲基丙烯酸羟乙酯、三羟甲基丙烷、季戊四醇、甘露醇和山梨醇等和L-丙交酯反应，得到末端为羟基的线形和星形聚L-丙交酯。

The morphologies formed were characterized by SEM and DLS methods, and spherical particles with various sizes were observed.5. To obtain a amphiphilic dumbbell-shaped copolymer, we successfully synthesized dendritic-linear-dendritic triblock copolymers composed of linear polystyrene and poly dendrons.

树枝状共聚物最外层PSt-PNAS链段利用乙二胺和NAS活性酯的取代反应交联，同时，中间的聚丙交酯段被降解，得到纳米空心球，用SEM和DLS进行观测和表征。5。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。