私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

相關鏈接
聯系方式
  • 通信地址:杭州市浙大路38號浙大玉泉校區第十教學大樓(石化大樓)4111室
  • 郵編:310027
  • 電話:0571-87952631
  • 傳真:0571-87951612
  • Email:wulinbo@zju.edu.cn
當前位置:> 首頁 > 論文著作 > 正文
Poly(L-lactic acid)/silicone dioxide nanocomposites prepared via in situ melt polycondensation of L-lactic acid in the presence of acidic silica sol: Dispersion stability of nanoparticles during dehydration/oligomerization.
作者:Zhaoqin Ma, Linbo Wu*, Bo Peng.
關鍵字:biodegradable, nanocomposites, polycondensation
論文來源:期刊
具體來源:Journal of Applied Polymer Science 124: 3980–3987, 2012.06.05
發表時間:2012年

In this work, the stability of nanoparticles
during the dehydration/oligomerization (D/O) stage in
situ melt polycondensation of L-lactic acid to prepare
poly(L-lactic acid) (PLLA)/SiO2 nanocomposite was studied.
The change in the appearance of the reaction mixture
was tracked, and the resultant oligo(L-lactic acid) (OLLA)/
SiO2 and PLLA/SiO2 nanocomposites were characterized
by transmission electron microscopy, 1H-NMR, and light
transmittance. The electric double layer and the grafted
OLLA chains provided static and steric stabilities during
the early and late phases, respectively. However, there
existed an intermediate transitional phase with weak stability
when the static stability was weakened, but sufficient
steric stability had not yet been established; this led
to soft or hard aggregation, depending on the SiO2 loading
and agitation conditions. At low or moderate SiO2
loading (<5–10%), the soft aggregation could be depressed
with appropriate agitation conditions and redispersed
with the aid of gradually established steric interaction
energy. Consequently, well-dispersed PLLA/SiO2 nanocomposites
with SiO2 loadings of 5 and 10% were successfully
prepared by in situ melt polycondensation with an
arc stirrer at 400 and 600 rpm, respectively, during the D/
O stage.

主站蜘蛛池模板: 肥东县| 托克逊县| 中山市| 阿拉尔市| 贵定县| 海南省| 营口市| 多伦县| 陆丰市| 太谷县| 桂东县| 海宁市| 云安县| 桦南县| 合阳县| 东光县| 丹江口市| 泽普县| 诸暨市| 韶关市| 肥西县| 和林格尔县| 永宁县| 黔南| 察隅县| 印江| 年辖:市辖区| 长海县| 阿巴嘎旗| 沁源县| 教育| 钟山县| 德清县| 乌鲁木齐县| 兴义市| 应城市| 巴彦淖尔市| 高雄市| 温州市| 新宾| 湖南省|