高性能/高温聚合物(Ⅴ)反应性端基聚酰亚胺齐聚物及固化技术

综述了高性能/高温聚合物中的反应性端基齐聚物与热固性聚酰亚胺及其固化技术,其包括PMR-15、PMR-Ⅱ,端乙炔基聚酰亚胺、苯乙炔封端聚酰亚胺、Thermcon聚酰亚胺、其它热固性聚酰亚胺、苯并环丁烯端基聚酰亚胺,对其化学结构与性能的关系也进行了讨论。     

高性能/高温聚合物(Ⅴ)反应性端基聚酰亚胺齐聚物及固化技术

综述了高性能/高温聚合物中的反应性端基齐聚物与热固性聚酰亚胺及其固化技术,其包括PMR-15、PMR-Ⅱ,端乙炔基聚酰亚胺、苯乙炔封端聚酰亚胺、Thermcon聚酰亚胺、其它热固性聚酰亚胺、苯并环丁烯端基聚酰亚胺,对其化学结构与性能的关系也进行了讨论。     

高性能/高温聚合物的设计、性能和应用进展(Ⅵ)其他反应性端基及链内乙炔基齐聚物及其固化

综述了诸如星形支化苯乙炔封端苯并喹喔啉齐聚物、苯乙炔端基芳醚聚合物、烯丙基聚苯醚、含庞大芴基的聚芳醚等反应性端基芳醚齐聚物,主链含乙炔单元的聚(酰胺-酰亚胺)、马来酰亚胺端基聚合物,热塑性塑料增韧双马来酰亚胺和超支化聚醚酰亚胺的合成、性能和固化技术。     

热固性聚酰亚胺展望

本文评述了降冰片烯、乙炔、苯并环丁烷和马来酸酐封端的热固性聚酰亚胺的发展现状,并介绍了他们的发展趋势及应用前景.     

基于降冰片烯酸酐的酰亚胺封端剂的研究进展

降冰片烯酸酐封端PMR聚酰亚胺具有优良的加工性能、热稳定性能和力学性能,被广泛运用于航空航天等高温领域。综述了降冰片烯酸酐封端PMR聚酰亚胺的交联结构和热分解,以及封端剂的优化的研究进展。展望了封端聚酰亚胺和封端剂未来的发展方向。     

降冰片烯与乙炔基官能化苯并恶嗪单体研究

采用溶剂法合成了含有降冰片烯和乙炔基团的苯并恶嗪单体(oHPNI-ac)。通过核磁共振氢谱(~1H-NMR)和傅里叶变换红外光谱(FT-IR)证实了其分子结构,并以示差扫描量热分析(DSC)和原位红外图谱(in situ FT-IR)揭示了其固化行为。结果表明,oHPNI-ac的起始固化温度为205℃,固化峰值温度为224℃。oHPNI-ac中降冰片烯的碳碳双键与乙炔基的碳碳三键可在恶嗪环开环聚合过程中交联,从而降低了降冰片烯双键的固化温度。通过Kissinger方法和Ozawa方法计算得到该苯并恶嗪活化能分别为94.6,97.1 kJ/mol,且推测得到该单体的固化反应动力学方程。     

含醚键结构双马来酰亚胺体系固化动力学及耐热性能的研究

采用差示扫描量热法(DSC)和热失重法(TGA)详细研究了新型双马来酰亚胺(BMI)树脂体系的固化反应和耐热性能.研究结果表明,BMPN(2,7-二(4-马来酰亚胺)苯醚基萘)树脂由于萘环结构的存在,在固化反应及耐热性能方面与BMPB(1,4二(4-马来酰亚胺)苯醚基苯)、BMPA(4,4'-二(4-马来酰亚胺)苯醚基...     

3，3’-二乙基-4，4’-二苯甲烷型多马来酰亚胺／聚苯醚树脂的固化反应研究

热固性聚苯醚(PPO)已成为高性能印制电路板用树脂(PCB)发展的主流。本课题组的前期研究表明,3,3,-二乙基-4,4,-二苯甲烷型多马来酰亚胺(PEDM)/烯丙基化PPO是一种新型高性能PCB用树脂。文章采用红外光谱和裂解气相色谱,对PEDM的含量为PPO 10%的PEDM/烯丙基化PPO树脂的固化反应进行研究,结果表明,PEDM分子的不饱和双键与PPO的烯丙基和羟基在加热过程中发生了反应。     

苯乙炔苯酐型热固性聚酰亚胺的合成与表征

热固性聚酰亚胺是一类先进复合材料基体树脂,相对于热塑性聚酰亚胺具有更高的耐温等级和更好的加工性能,因而作为树脂基复合材料和黏结剂在航空航天等领域应用更为成功。4-苯乙炔苯酐及其衍生物兼具有聚酰亚胺所必需的黏结性、耐热性和机械强度,其利用价值极高,是航空航天用复合材料母体树脂的原料。     

降冰片烯酰亚胺型双苯并嗪的合成及性能

首先用降冰片烯二酸酐、对氨基苯酚为原料合成降冰片烯酰亚胺(NI),然后用合成的NI、4,4-二氨基二苯醚(ODA)和多聚甲醛为原料进行Mannich反应合成出降冰片烯酰亚胺型双苯并嗪(NI-BOZ),经高温固化后形成热固性树脂。用FTIR、1H NMR、13C NMR分析了NI和NI-BOZ的化学结构,证实了所得的目标产物;用DSC对NI-BOZ的固化动力学进行研究;用DMA和TGA分析了NI-BOZ的固化物的热性能。结果表明:NI-BOZ的固化反应活化能为86.27 k J·mol-1,反应级数为0.91;poly(NI-BOZ)树脂空气条件下的玻璃化转变温度为215℃,氮气条件下失重5%的温度为445℃,失重10%的温度为467℃,在800℃的残碳率为63%。     

Surface reactivity of polyimide and its effect on adhesion to epoxy

Polyimides are commonly used as organic passivation layers for microelectronic devices due to their unique combination of properties such as low dielectric constant, high thermal stability, excellent mechanical properties and superior solvent resistance. Unfortunately, polyimides are well known to be difficult to bond to other materials, especially to epoxy resins. Many surface treatments have been developed to increase epoxy–polyimide adhesion. These treatments include exposure to ion beams, plasmas and chemical solutions. The goal of our research was to relate surface reactivity of epoxy and polyimide resins to the strength of epoxy–polyimide interfaces. The surface reactivity of four polyimides was studied and quantified using contact angle measurements, flow microcalorimetry (FMC), Fourier transform infrared (FT-IR) spectroscopy (using an attenuated total reflection (ATR) accessory) and X-ray photoelectron spectroscopy (XPS). Several ways of analyzing contact angles were tried and only a weak correlation between the polar component or the acid–base components of the surface free energy with the critical interfacial strain energy release rate (i.e., the interfacial fracture strength) was observed. FMC results suggest that the strength of epoxy–polyimide interfaces is related to the molecular interactions between the curing agent and polyimide. The molecular interactions between the curing agent and polyimide surfaces were found to be either greater than epoxy and polyimide interactions or more irreversible. Therefore, the curing agent (2,4-EMI) is thought to play a critical role in controlling adhesion strength.     

高性能树脂基覆铜板的研究进展

对高性能新型环氧树脂、双马来酰亚胺、氰酸酯等热固性树脂及聚苯醚、聚四氟乙烯、聚酰亚胺等热塑性树脂基覆铜板的近况及发展进行了综述。对用于覆铜板的新型环氧树脂体系、环氧固化体系、环氧改性剂的应用进行了重点阐述,并指出发展覆铜板的关键是加强高性能树脂基体的研究,即研制具有高耐热性、优异介电性能、阻燃环保性、能阻挡紫外光和具有自动光学检测功能等特性的树脂是今后的发展方向。     

Molecular weight controlled poly(amic acid) resins end‐capped with phenylethynyl groups for manufacturing advanced polyimide films

To investigate the effect of reactive end‐capping groups on film‐forming quality and processability, a series of molecular weight‐controlled aromatic poly(amic acid) (PAA) resins functionalized with phenylethynyl end groups were prepared via the polycondensation of 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA), para ‐phenylenediamine (PDA), and 4‐phenylethynyl phthalic anhydride (PEPA) served as molecular‐weight‐controlling and reactive end capping agent. The PAA resins with relatively high concentrations endow enhanced wetting/spreading ability to form PAA gel films by solution‐cast method which were thermally converted to the fully‐cured polyimide (PI) films. The mechanical and thermal properties of PI films were investigated as a function of PAA molecular weights (M_n ) and thermal‐curing parameters. Mechanical property, dimensional stability and heat resistance of the fully‐cured PI films with PAA M_n > 20 ×10³ g mol^?1 are found to be better than that of their unreactive phthalic end‐capped counterparts. The covalent incorporation of chain‐extension structures in the backbones, induced by thermal curing of phenylethynyl groups, might facilitate yielding a higher degree of polymer chain order and consequently improved resistance strength and elongation at break to tensile plastic deformation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45168.     

Investigation of the crosslinking efficiency of some additional curing polyimides

The thermal properties of a PMR (polymerization of monomer reactants) polyimide resin chain terminated with various reactive monomers has been studied. Vinyl groups appear as efficient as ethynyl in providing crosslinks that are more thermally stable than those resulting from nadic ester endcapping. Terminal nitrile groups were found to be unreactive. Evidence for the curing mechanism of these resins is presented from infrared, thermogravimetric, and liquid chromatographic analyses.     

Effects of dianhydrides on the thermal behavior of linear and crosslinked polyimides

To determine the thermal characteristics of linear and crosslinked polyimides (PIs), BTDA, ODPA, and 6FDA were used to synthesize polyimides. Thermal degradation temperature and glass transition temperature of the resulting PIs were measured using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). To measure the change in modulus and coefficient of thermal expansion (CTE) depending on dianhydride structure, a dynamic mechanical analyzer (DMA) and thermo‐mechanical analyzer (TMA) were used. The thermal degradation and glass transition temperature properties of linear PIs varied according to whether the linear chain adopted a bulky or flexible structure. Dynamic modulus and thermal expansion values of linear polyimides also showed good agreement with the TGA and DSC results. As we expected, linear polyimide with bulky 6FDA groups showed better thermal behavior than the flexible polyimides. Crosslinked polyimide nadic end‐capped (norbornene) with a bulky dianhydride group had a lower thermal degradation temperature and higher CTE than flexible BTDA and ODPA polyimides. Our results indicate that the mobility of the dianhydride group affects the thermal behaviors of linear and crosslinked polyimides in different ways. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41412.     

Preparation and Characterization of Aminopropylsilatrane Endcapped Polyimide Films

γ-Aminopropylsilatrane (APS)/γ-aminopropyltriethoxysilane (APTES) end capped polyimide films were prepared by thermal imidization method. Polyamic acid (PAA) was prepared by the reaction of 4,4′-oxydianiline (ODA) with 4,4′-oxydipthalicdianhydride (ODPA) using dimethylacetamide (DMAc) as solvent. The end group of prepared PAA was capped by different percentage of APS/APTES. The polyimide films were characterized by different advanced instrumental techniques for chemical/physical properties. APS end capped PI films show better thermal and mechanical properties and air permeability than APTES end capped polyimide films.     

High temperature polyimides,chemistry and properties

Selected polyimide resins are capable of long term use at 316°C for over thousands of hours in an inert atmosphere, and approximately 2000 hours in air. This attractive feature of polyimides has provided an avenue for applications at elevated temperature (316°C) as adhesives, coatings, and secondary structures in the form of fiber reinforced polyimide composites. The chemistry and properties of thermoplastic and crosslinked polyimides, including addition-type polyimides, will be discussed. The chemical considerations of both commercial and experimental polymer materials, Avimid N, PMR-15, LARC TPI, IP-600, L-20, and L-30 as they affect processing are reviewed. General physical, thermal, mechanical, and thermo-oxidative stability properties of polyimides are presented Room temperature and 316°C mechanical properties of unaged and 1000 hr 316°C aged high temperature polymer composites will also be discussed.     

Adhesion mechanisms in the solid‐state bonding technique using submicrometer aromatic thermosetting copolyester adhesive

The adhesion mechanism between polyimides and aromatic thermosetting copolyester (ATSP) involved in the solid‐state bonding technique using submicrometer ATSP coatings was evaluated. The adhesion strength at the interface between ATSP and polyimide is strongly related to the diffusion of ATSP into the polyimide base layer. We used dynamic secondary ion mass spectrometry to study the interface width between deuterated ATSP and polyimides and found that the interface between ATSP and poly(4,4′‐diphenylether pyromellitimide) (PMDA‐ODA) is wider than the interface between ATSP and poly(p‐phenylene biphenyltetracarboximide) (BPDA‐PPD) because of the less rigid chain in the PMDA‐ODA. By partially curing both polyimides, the interface width was greatly increased, which could lead to an improved adhesion at the interface between polyimide BPDA‐PPD and ATSP. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3843–3856, 2004