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1、Analysis of Molecular Aggregation Structures of Fully Aromatic andSemialiphatic Polyimide Films with Synchrotron Grazing IncidenceWide-Angle X-ray Scattering,Reading Report,Macromolecules 2010, 43, 19301941,Junji Wakita, Sangwoo Jin, Tae Joo Shin, Moonhor Ree,*, and Shinji Ando*,2010年5月29日,2010.05.2
2、9,Contents,2010.05.29,Introduction,5,2010.05.29,晶态中，PI分子链中二酐与二胺链节部分对应规整排列，没有相对无序，这种结构称为“优先层堆砌”（PLP）；近晶态结构中，分子链之间堆砌则为相对无序。,2010.05.29,a = 8.57, b = 5.51, and c (fiber axis) = 16.78.,16.78,2010.05.29,Introduction,PI薄膜在分子水平上的聚集态结构还不十分清楚；,目前对于这种近晶有序区的分子链间堆砌没有报道；,用一维XRD很难分析PI薄膜的各向异性；,two-dimensional (2D)
3、 grazing incidence X-ray scattering (GIXS)measurement,一般地，PI薄膜没有确定的结晶衍射峰，这是因为它们缺乏大尺寸的三维有序结构，这种相对无序区称之谓介于晶体与无定型之间的“近晶态有序结构区”。,XRD没有用来表征半脂肪聚酰亚胺的聚集态结构。,2010.05.29,Experiment Section,2010.05.29,Experiment Section,Materials Pyromellitic dianhydride (PMDA), 4,4-oxidiphthalic anhydride (ODPA), 3,3,4,4-biph
4、enyltetracarboxylic anhydride (BPDA),2,2-Bis(trifluoromethyl)-4,4-diaminobiphenyldiamine (TFDB), 4,4-Diaminocyclohexylmethane (DCHM)4,4-Diaminodiphenyl ether (ODA)N,O-Bis(trimethylsilyl)trifluoroacetamide (99%, BSTFA) (,N,O-双(三甲基硅烷基)三氟甲基乙酰胺,2010.05.29,Experiment Section,Preparation of Polyimide Film
5、s： 芳族聚酰亚胺薄膜的制备半脂肪聚酰亚胺薄膜的制备,芳香二胺+二酐,DMAc,48h,PAA,DCHM,BSTFA,DMAc,二酐,48h,PASE,70/Ih+300 /1.5h,70/Ih+300 /1.5h,Ar-PIs,Al-PIs,2010.05.29,Experiment Section,半脂肪聚酰亚胺的制备,2010.05.29,Measurement,What is 2D Grazing Incidence Wide-Angle X-ray Scattering (GIWAXS)?,2010.05.29,Quantum Chemical Calculation,The den
6、sity functional theory (DFT) with a three-parameter Becke-style hybrid functional(B3LYP)55-57 with 6-311G(d) basis；All calculations were performed with a Gaussian-03 D.0258 program package installed in the Global Scientific Information and Computing Center (GSIC), Tokyo Institute of Technology.,2010
7、.05.29,Results and Discussion,全芳香聚酰亚胺,The out-of-plane and in-plane 1DGIWAXSprofiles extracted along the af direction at 2f = 0 and 2f direction at af = 1.03o from the 2D GIWAXS patterns,2010.05.29,(a) af=17.2, (b) 15.8,and (c) 14.3)(azimuthal profile) are shown in Figure 5c.u=90o说明分子链优先沿平行于薄膜平面方向排列
8、。,Figure 5. GIWAXS profiles of Ar-PIs: (a) out-of-plane profiles, (b) in-plane profiles, and (c) azimuthal profiles at the ch-pack peak,无定峰强度 ：PMDA/PDA PMDA/TFDB PMDA/ODA,说明：线性平面分子有利于形成更加有序的结构,2010.05.29,全芳香聚酰亚胺,2010.05.29,芳香聚酰亚胺的聚集态为：近晶态+无定型态，缺乏长程的三维有序区；分子链轴优先沿平行于薄膜平面排列。,全芳香聚酰亚胺,2010.05.29,半脂肪聚酰亚胺,
9、The out-of-plane and in-plane 1DGIWAXSprofiles extracted along the af direction at 2f = 0 and 2f direction at af = 1.03o from the 2D GIWAXS patterns,2010.05.29,out-of-plane profiles, (a) af = 15.0, (b) 15.1, (c) 15.2and the in-planeprofiles , (a) 2f=4.7, (b) 4.1, (c) 4.1),无定峰强度 ：PMDA/DCHM BPDA/DCHM
10、ODPA/DCHM,说明：二酐的化学结构对其聚集态结构影响很大。,2010.05.29,半脂肪聚酰亚胺,2010.05.29,半脂肪聚酰亚胺,2010.05.29,Tg：ODPA/DCHM (258 ) BPDA/DCHM (278 )PMDA/DCHM (320 )Ti=300,半脂肪聚酰亚胺,2010.05.29,不同的结构，PI分子链形成的有序区堆砌结构不同,半脂肪聚酰亚胺,2010.05.29,芳香聚酰亚胺与半脂肪聚酰亚胺聚集态结构对比,PMDA/DCHM相对PMDA/ODA具有更高的有序程度,002,004,002,2010.05.29,Conclusions,所有聚酰亚胺的聚集态结
11、构都是由无定型区和近晶有序区构成，本文分析了四类特征衍射峰：amorphous halo, packing of PI chains, -stacking of imide and phenyl rings, and repeating periodicity along PI chains.在有序区，芳香聚酰亚胺分子链沿薄膜平面和平面外取向排列，其聚集态结构主要受其立体结构影响；尽管半脂肪聚酰亚胺具有弯曲的分子结构，但其分子链间有序程度高于芳香聚酰亚胺，而且有序程度PMDA/DCHM BPDA/DCHM ODPA/DCHM，表明在热酰亚胺化过程中的分子链重排对其聚集态结构有更大影响，这种重排
12、导致有序结构的各向异性。2D-GIWAXS对表征形成在基材上的薄膜的聚集态结构是有效的。,2010.05.29,My Benefits and Questions- My Benefits,2010.05.29,My Benefits and Questions- My Questions,作者认为半脂肪聚酰亚胺的有序程度高于芳香聚酰亚胺的有序程度是因为其玻璃化温度低于酰亚胺化温度而进行的分子链重排造成的，为什么不对芳香聚酰亚胺在高于玻璃化温度的范围内进行处理后对比？这样是不是更有说服力？升温处理后，会不会有出现类似于半脂肪聚酰亚胺出现的有序区结构各向同性现象呢？,2010.05.29,My Questions,本文作者用无定型峰的强度大小来表征有序程度的大小，认为无定型峰强度大，有序程度就低，那么无定型峰强度越小，是不是说有序程度就越大呢？因为有些PI薄膜的XRD图中根本就只有很小的一个弥散峰。,Thank You !,
