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Rheology of miscible polymer blends with hydrogen bonding.

机译：具有氢键的可混溶聚合物共混物的流变学。

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摘要

Poly(4-vinylphenol) (PVPh) was blended with four different polymers: poly(vinyl methyl ether) (PVME), poly(vinyl acetate) (PVAc), poly(2-vinylpyridine) (P2VP), and poly(4-vinylpyridine) (P4VP) by solvent casting. The miscibility of these four PVPh-based blend systems was investigated using differential scanning calorimetry (DSC) and the composition-dependent glass transition temperature (Tg) was predicted by a thermodynamic theory. The hydrogen bonds between phenolic group in PVPh and ether group, carbonyl group or pyridine group was confirmed by Fourier transform infrared (FTIR) spectroscopy. The fraction of hydrogen bonds was calculated by the Coleman-Graf-Painter association model. Linear dynamic viscoelasticity of four PVPh-based miscible polymer blends with hydrogen bonding was investigated. Emphasis was placed on investigating how the linear dynamic viscoelasticity of miscible polymer blends with specific interaction might be different from that of miscible polymer blends without specific interaction. We have found that an application of time-temperature superposition (TTS) to the PVPh-based miscible blends with intermolecular hydrogen bonding is warranted even when the difference in the component glass transition temperatures is as large as about 200°C, while TTS fails for miscible polymer blends without specific interactions. On the basis of such an observation, we have concluded that hydrogen bonding suppressed concentration fluctuations in PVPh-based miscible blends. It has been found that both the intra-association (self-association) of the phenoxy hydroxyl groups in PVPh and inter-association (intermolecular interactions) between the constituent components have a profound influence on the frequency dependence of dynamic moduli in the terminal region of the PVPh-based miscible blend systems investigated.; Hydrogenated functional polynorbornenes (HFPNBs) were synthesized and they were used to investigate the miscibility and rheology of HFPNB-based miscible blends with hydrogen bonding. Specifically, functional norbornenes with carboxylic (-COOH) group or hydroxyl (-OH) group were first synthesized and then they were polymerized, via ring-opening metathesis polymerization followed by hydrogenation, to obtain HFPNBs, HPNBCOOH and HPNBOH. Subsequently, the miscibility of binary blends consisting of (1) HPBNCOOH and polycarbonate (PC), (2) HPBNCOOH and poly(2-vinylpyridine) (P2VP), and (3) HPBNOH and PC was investigated using DSC and FTIR spectroscopy. It has been found that both PC/HPBNCOOH and P2VP/HPBNCOOH blend systems exhibit a broad, single glass transition over the entire blend compositions as determined by DSC, indicating that the respective blend systems are miscible, and they form hydrogen bonds as determined by FTIR spectroscopy. On the other hand, PC/HPBNOH blends were found to exhibit two glass transition temperatures, indicating that the blends are not miscible. The dynamic oscillatory shear rheometry has shown that reduced log G' versus log aTo and log G" versus log aTo plots, and also log G' versus log G" plots of PC/HPBNCOOH and P2VP/HPBNCOOH blend systems are independent of temperature. We have concluded that an application of TTS to the miscible polymer blends with hydrogen bonding is warranted although the difference in component glass transition temperatures is as large as 91C for the PC/HPNBCOOH blend system.
机译：将聚（4-乙烯基苯酚）（PVPh）与四种不同的聚合物共混：聚（乙烯基甲基醚）（PVME），聚（乙酸乙烯酯）（PVAc），聚（2-乙烯基吡啶）（P2VP）和聚（4-乙烯基吡啶）（P4VP）通过溶剂浇铸。使用差示扫描量热法（DSC）研究了这四种基于PVPh的共混体系的混溶性，并通过热力学理论预测了成分相关的玻璃化转变温度（Tg）。通过傅里叶变换红外光谱（FTIR）证实了PVPh中酚基与醚基，羰基或吡啶基之间的氢键。氢键的分数通过Coleman-Graf-Painter缔合模型计算。研究了四种具有氢键的基于PVPh的可混溶聚合物共混物的线性动态粘弹性。重点放在研究具有特定相互作用的可混溶聚合物共混物的线性动态粘弹性与没有特定相互作用的可混溶聚合物共混物的线性动态粘弹性如何不同。我们发现，即使当组分玻璃化转变温度的差异大到约200°C时，也需要将时间-温度叠加（TTS）应用于具有分子间氢键的PVPh基可混溶共混物，而TTS不能用于没有特定相互作用的可混溶聚合物共混物。基于这种观察，我们得出结论，氢键抑制了基于PVPh的可混溶共混物的浓度波动。已经发现，PVPh中苯氧基羟基的内部缔合（自缔合）和构成成分之间的缔合（分子间相互作用）都对P末端的动态模量的频率依赖性产生深远的影响。基于PVPh的混溶共混体系的研究。合成了氢化功能聚降冰片烯（HFPNBs），并用于研究具有氢键的基于HFPNB的可混溶共混物的可混溶性和流变性。具体地，首先合成具有羧基（-COOH）或羟基（-OH）的官能降冰片烯，然后通过开环易位聚合然后氢化将它们聚合，以获得HFPNB，HPNBCOOH和HPNBOH。随后，使用DSC和FTIR光谱研究了由（1）HPBNCOOH和聚碳酸酯（PC），（2）HPBNCOOH和聚（2-乙烯基吡啶）（P2VP）以及（3）HPBNOH和PC组成的二元共混物的混溶性。已经发现，PC / HPBNCOOH和P2VP / HPBNCOOH共混体系在DSC所确定的整个共混物组成中均表现出宽广的单玻璃化转变，表明各个共混体系是可混溶的，并且通过FTIR确定它们形成氢键光谱学。另一方面，发现PC / HPBNOH共混物表现出两个玻璃化转变温度，表明该共混物不可混溶。动态振荡剪切流变法表明，PC / HPBNCOOH和P2VP / HPBNCOOH共混体系的log G'相对于log aTo和log G“相对于log aTo的曲线减小，log G'相对于log G”的曲线也与温度无关。我们已经得出结论，尽管PC / HPNBCOOH共混体系的组分玻璃化转变温度之差高达91℃，但仍应将TTS应用于具有氢键的可混溶聚合物共混物。

著录项

  • 作者

    Yang, Zhiyi.;

  • 作者单位

    The University of Akron.;

  • 授予单位 The University of Akron.;
  • 学科 Engineering Materials Science.; Plastics Technology.
  • 学位 Ph.D.
  • 年度 2007
  • 页码 233 p.
  • 总页数 233
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 工程材料学;整形外科学（修复外科学）;
  • 关键词

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