高等学校化学学报
高等學校化學學報
고등학교화학학보
CHEMICAL JOURNAL OF CHINESE UNIVERSITIES
2014年
2期
440-448
,共9页
T形三组分双亲分子%相行为%耗散粒子动力学模拟
T形三組分雙親分子%相行為%耗散粒子動力學模擬
T형삼조분쌍친분자%상행위%모산입자동역학모의
T-shaped ternary amphiphilie%Phase behavior%Dissipative particle dynamics simulation
采用耗散粒子动力学方法建立了以侧链长度和温度为变量的相图,计算了相关结构参数及每个液晶相对应侧链的有效体积分数,重现了实验上观察到的五边形、六边形柱状相及刚棒在层内位置的有序堆垛层状结构。研究发现,长棒状T形三组分双亲分子相图中的相序列和相结构符合相关报道,并且侧链有效体积分数fL与实验值一致。表明粗粒化模型反映了真实T形分子的主要特性,如分子的拓扑结构、排除体积效应及分相趋势、刚棒液晶基元的长径比和侧链的空间效应。证实了侧链尺寸对主/侧链非线性连接体系的自组装结构及各组成单元的位置分布的重要作用。
採用耗散粒子動力學方法建立瞭以側鏈長度和溫度為變量的相圖,計算瞭相關結構參數及每箇液晶相對應側鏈的有效體積分數,重現瞭實驗上觀察到的五邊形、六邊形柱狀相及剛棒在層內位置的有序堆垛層狀結構。研究髮現,長棒狀T形三組分雙親分子相圖中的相序列和相結構符閤相關報道,併且側鏈有效體積分數fL與實驗值一緻。錶明粗粒化模型反映瞭真實T形分子的主要特性,如分子的拓撲結構、排除體積效應及分相趨勢、剛棒液晶基元的長徑比和側鏈的空間效應。證實瞭側鏈呎吋對主/側鏈非線性連接體繫的自組裝結構及各組成單元的位置分佈的重要作用。
채용모산입자동역학방법건립료이측련장도화온도위변량적상도,계산료상관결구삼수급매개액정상대응측련적유효체적분수,중현료실험상관찰도적오변형、륙변형주상상급강봉재층내위치적유서퇴타층상결구。연구발현,장봉상T형삼조분쌍친분자상도중적상서렬화상결구부합상관보도,병차측련유효체적분수fL여실험치일치。표명조립화모형반영료진실T형분자적주요특성,여분자적탁복결구、배제체적효응급분상추세、강봉액정기원적장경비화측련적공간효응。증실료측련척촌대주/측련비선성련접체계적자조장결구급각조성단원적위치분포적중요작용。
Using dissipative particle dynamics simulations, a phase diagram in terms of temperature and lateral chain length was established, related structural parameters and the effective volume fraction of lateral chains fL related to each mesophase were calculated. The experimentally observed pentagonal, hexagonal co-lumnar phase and the lamellar phase where rods are stacked with in-plane order are firstly reproduced. The re-sults show that the phase sequence and structures in the diagram of T-shaped ternary amphiphilies with long rod-like mesogens agree well with previous reports, the effective volume fraction of lateral chains fL related to each mesophase is also quantitatively consistent with the experimental value. These combined results demon-strate that the coarse graining model in our simulation reflects essential structural features of T-shaped real mo-lecules like molecular topology, excluded volume effects, tendency to phase separation, the length-to-width ra-tio of rod liquid crystal unit and the spatial effects of lateral chains, and they also confirm the fact that the size of lateral chains plays an important role in affecting the self-assembled structures of nonlinear systems and the distribution of each constituent.