酚酞型聚芳醚砜(Ⅶ):K_2C0_3存在下PP/DCDPS体系聚合反应机理的研究

利用~(13)C-NMR方法研究了弱碱K_2CO_3存在下酚酞成盐反应及其与活性双卤砜亲核缩聚反应过程中的结构特征。对一系列碱性条件下酚酞(PP)与4,4'-二氯二苯砜(DCDPS)的缩聚反应的研究表明任何影响内酯结构酚酞盐生成的因素都会严重阻碍聚合反应的进行。对模型化合物存在下K_2CO_3在极性非质子溶剂中的溶解/解离行为的研究结果表明酚酞类Card。双酚与固体K_2CO_3之间可能存在着一种特殊的络合作用。基于我们系列研究结果,本文中总结提出了弱碱K_2CO_3存在下酚酞的反应机理。     

Encapsulation of Phenolphthalein pH-Indicator into a Sol-Gel Matrix

Transparent monolithic silica doping with phenolphthalein has been prepared via the acid-catalyzed sol-gel reactions of tetraethylorthosilicate in the presence of phenolphthalein. The immobilized phenolphthalein pH-indicator shows similar behavior as its solution counterpart. The UV/Vis spectra indicate that the phenolphthalein retains its structure during the sol-gel reactions in terms of response to pH. The phenolphthalein can be regarded as uniformly distributed in the silica matrix. This observation has been confirmed using polarized microscopy.     

Polymeric pH indicators immobilized PVA membranes for optical sensors of high basicity based on a kinetic process

Two kinds of polymeric pH indicators PPF (phenolphthalein-formaldehyde product) and CPF (o-cresolphthalein-formaldehyde product) immobilized cross-linked poly(vinyl alcohol) membranes (PPF-PVA and CPF-PVA) for optical intermittent determination of high basicity ([OH⁻] = 1-8 M) based on a kinetic process were developed. In our previous work, we had demonstrated that PPF-PVA and CPF-PVA could perform the determination of high pH values from pH 10.0 to 14.0. Here the discoloring kinetic behaviors of PPF-PVA and CPF-PVA were compared with those of free phenolphthalein, o-cresolphthalein and thymolphthalein. Experimental results and theoretical analysis indicated that the response behaviors of the optodes’ membranes in concentrated NaOH solutions were diffusion-independent and still complied with the pseudo-first-order kinetics. In addition, two data analysis methods for determination were presented. One was directly based on the reduced absorbance; the other was based on the discoloring kinetic constant. It was found that the latter could perform a rapid (60 s) and reliable (relative standard deviation: 2.6%) determination for high basicity. These kinds of optodes can be used repeatedly when they are immersed in low-pH solutions to regain the protonated form after each determination.     

动态光散射对良溶剂中酚醛型聚醚砜的研究

用动态光散射方法研究了酚酞型聚醚砜(PES-C)在良溶剂DMF中的稀溶液性质。在稀溶液中,PES-C分子由于内旋转发生链折叠,整体上表现出柔性链的性质,较好的符合球形模型;而分子链的局部刚性结构又使分子尺寸稳定;它的扩散行为随温度的变化符合Arrehnius方程。表征了PES-C分子在稀溶液中的形态结构,且给出了PES-C分子在DMF中的扩散系数、扩散活化能、无限稀时的扩散系数和流体力学半径等重要特征参数。     

SPEEK/PES-C、SPEEK/SPES-C共混质子交换膜研究

通过在磺化聚醚醚酮（SPEEK,DS=61.68%）中分别混入酚酞型聚醚砜（PES-C）、磺化酚酞型聚醚砜（SPES-C,DS=53.7%）制备出SPEEK/PES-C、SPEEK/SPES-C共混质子交换膜.结果表明,共混的两种聚合物之间均具有较好的相容性.PES-C、SPES-C的混入能有效降低膜的溶胀及甲醇透过,且随着共混量的增加,这种作用越趋明显.纯SPEEK膜在75℃左右溶解,而SPEEK/PES-C（30 wt%）、SPEEK/SPES-C（30 wt%）共混膜在80℃时溶胀度仅为22.5%、26.32%.在室温至80℃范围内,纯SPEEK及共混膜的甲醇透过系数都在10-7 cm2·s-1数量级上,远小于Nafion 115膜.在饱和湿度下,温度大于90℃时,SPEEK/PES-C（20 wt%）共混膜电导率超过Nafion115 膜;温度大于110℃时,SPEEK/SPES-C（30 wt%）共混膜电导率与Nafion 115膜相当,达到 0.11 S·cm-1.高电导率,低透醇系数以及明显提高了的可使用温度表明该类共混膜有望在DMFC中使用.     

一种含酞侧基的聚醚醚酮与有机溶剂之间的相互作用

用反相色谱法研究了一种新型含酞侧基的聚醚醚酮(PEK-C)在玻璃化转变温度以下(150℃和180℃)与29种常用溶剂之间的相互作用。从这些溶剂中区分和筛选出了PEK-C的溶剂,溶胀剂及沉淀剂,用以指导PEK-C的溶解加工和膜的制备。本研究也证明了Dangayach等用色谱法研究高聚物的溶解性是一个方便的方法。     

酚酞型聚芳醚砜——Ⅱ.侧基结构对Cardo双酚聚合反应性的影响

基于在“一步法”聚合反应过程中发现的酚酞对反应有特殊的“自催化”作用,本文合成了几种具有与酚酞类似结构的Cardo双酚,并通过对其聚合反应规律的研究,进一步探讨“自催化”作用的本质。实验结果表明,这类Cardo双酚也较普通结构双酚更易于进行异相成盐反应,表现为其聚合反应速度的明显加快。     

一种含酚酞结构聚酰亚胺的合成及性能表征

通过酚酞的硝化和还原,得到了一种新型的含酞结构和酚羟基的二胺单体,通过二胺和4,4-六氟亚异丙基二(邻苯二甲酸酐) (6FDA)缩聚并高温亚胺化,得到了相应的含酚羟基聚酰亚胺PI-HP.利用1H-NMR、FTIR、GPC及热分析表征了PI-HP的结构和热性能,利用紫外-可见光谱表征了其透明性.结果表明,PI-HP在部分极性有机溶剂中如DMF、THF、丙酮中具有良好的溶解性,具有较高的热稳定性并在可见光区域具有较好的透明性,其含羟基可进一步修饰用于制备各种功能材料.     

Structural and fluorescence properties of phenolphthalein bridged cyclotriphosphazatrienes

This study dealt with the reactions of hexachlorocyclotriphosphazatriene, N₃P₃Cl₆ (trimer) (1) with phenolphthalein (2) to give the phenolphthalein bridged compounds 3, 4 and 5. The phenolphthalein bridged cyclotriphosphazatriene derivatives are reported for the first time. The new compounds (3–5) are characterized by elemental analysis, mass spectrometry, UV–vis, FT-IR, ¹H, ³¹P NMR and fluorescence spectroscopy. The more bridged phenolphthalein groups show the higher intensity of the absorption bands in the UV–vis spectra. Fluorescence spectrum of compound 3 shows a small band in the lower spectral range, while the spectra of compounds 4 and 5 show more intense and a band in higher spectral range.     

主链含酞和芴结构的无定形聚芳醚酮的合成

通过共聚改性在酚酞聚芳醚酮(PEK-C)的主链上引入含芴侧基,制备了一系列主链含酞和芴结构的线性高分子量无定形聚芳醚酮无规共聚物.通过傅里叶红外光谱(FTIR)、核磁共振谱(1H,13C NMR)等手段确定了共聚物结构.凝胶渗透色谱(GPC)数据表明,共聚物的Mn>6.0×104,Mw>1.0×105,PDI(Mw/Mn)范围在1.6~1.7之间.X射线衍射(XRD)数据表明共聚物系无定形结构,差示扫描量热法(DSC)和热重分析(TGA)测试表明聚合物具有良好的耐热性;初始热分解温度高于467℃;700℃时残炭率大于58.9%;共聚物呈现单一的玻璃化转变温度(Tg>243℃).当酚酞与双酚芴摩尔比在3∶7~5∶5范围时,共聚物的弹性模量和断裂伸长率显著提高,可分别达到3.1 GPa和58%,是酚酞聚芳醚酮的1.4倍和8.3倍.这类含酞和芴侧基的无定形聚芳醚酮保持了在氯仿、二氯甲烷、四氢呋喃(THF)和甲基吡咯烷酮(NMP)等极性非质子溶剂中良好的溶解性能,并显著提高了聚合物的力学性能和热性能.