含氟基团对聚酰胺酰亚胺非等温结晶动力学的影响

通过3,3′,4,4′-二苯醚四甲酸二酐(ODPA)和六氟二酐(6FDA)分别与11-氨基十一烷酸反应,合成了两种酰亚胺二酸单体,再用合成的酰亚胺二酸单体按照不同配比和对苯二胺反应合成了6FDA物质的量分数(在两种酰亚胺二酸单体中)分别为10%和25%的含氟共聚酰胺酰亚胺(PAI–F10和PAI–F25),同时按照相同工艺合成了不含6FDA的共聚酰胺酰亚胺(PAI–F0)。利用差示扫描量热仪测试了这3种聚合物的非等温结晶过程及其熔融行为,发现PAI–F10的结晶能力最强,其次为PAI–F0,PAI–F25的结晶现象不明显。采用Jeziorny法和Mo法分析了PAI–F0和PAI–F10的非等温结晶动力学,发现在较低降温速率下,PAI–F10生成晶体的能力更强,结晶度更高。进一步利用Kissinger方程求得PAI–F0和PAI–F10结晶活化能,发现PAI–F10具有更低的结晶活化能。以上研究结果表明含氟基团在低含量时可以促进聚酰胺酰亚胺的结晶能力,而在高含量时却抑制了聚酰胺酰亚胺的结晶。     

离子液体中光学活性聚酰胺酰亚胺的合成

聚酰胺酰亚胺作为重要的高性能材料应用广泛,如特种工程塑料。以L-丙氨酸和3,3’,4,4’-联苯四酸二酐为主要原料,利用以离子液体为介质的绿色合成方法制备了一种聚酰胺酰亚胺,并由正交试验得到最佳聚合条件。实验结果表明:该聚酰胺酰亚胺具有光学活性及一定的生物可降解性,良好的热稳定性,5%失重温度约367.5℃,600℃残余质量达61%,且在多种极性非质子溶剂都有较好的溶解性。     

聚酰胺弹性体研究进展

综述了聚酰胺热塑性弹性体的基本结构、种类、性能及未来的研究方向,重点介绍了聚酰胺热塑性弹性体的合成方法.聚酰胺热塑性弹性体的合成方法主要包括以下几种:二元酸合成法、异氰酸酯合成法、阴离子聚合合成法、一步合成法、酯交换法、动态硫化工艺这几类合成方法.并针对每一合成方法,分别阐述了其存在的问题,并对相应的问题提出了解决方案...     

光学纯氨基酸的工业化生产及展望

光学纯的氨基酸在制药工业和农业化学方面有着广泛的应用。主要介绍了抽提法和生物转化法生产氨基酸的研究进展以及几种重要氨基酸的合成方法。     

含氟聚酰胺酰亚胺自粘电磁线漆的合成与性能研究

合成了一种新型含氟二胺单体2-三氟甲基-4,4'-二氨基二苯醚(3FODA),该单体具有较高的反应活性和溶解性。使用3FODA替代4,4'-二胺基二苯醚(ODA),与偏苯三酸酐(TMA)、二甲苯甲烷二异氰酸酯(MDI)通过两步法合成了含氟聚酰胺酰亚胺自粘电磁线漆。试验证明,含氟基团三氟甲基的引入明显提高了漆膜的柔韧性和附着力。     

用二步法合成聚酰胺酰亚胺的研究

本文用偏苯三酸酐4—胺氯与4,4′—二氨基二苯醚,通过溶液缩合聚合反应,先合成聚酰胺酸,再经过热处理而得聚酰胺酰亚胺。并用红外光谱法、元素分析、热分析等方法,比较了聚酰胺酸和聚酰胺酰亚胺的组成、结构和性能。     

光学活性中间体化学合成技术进展

重点叙述了某些光学活性中间体的工业合成技术,包括手性氨基酸、手性羧酸、手性醇、手性胺和手性环氧化物.并介绍了本研究小组的Ugi碱新合成方法,双核二茂铁亚胺配体及新型环糊精手性固定相的制备和应用.     

旋光性聚酰胺研究进展

按化学结构对旋光性聚酰胺进行了分类,包括用非手性单体制备的旋光性酰胺、侧链含手性原子及主链含手性原子的旋光性聚酰胺。对旋光性聚酰胺的合成方法进行了总结,介绍了链增长缩聚法、溶液聚合法和界面缩聚法在合成旋光性聚酰胺方面的应用。     

专利

正一种家用电器电源线外护套用聚醚砜/聚酰胺酰亚胺复合材料及其制备方法公开号:CN105086453A公开日:2015-11-25申请人:天长市富信电子有限公司摘要:本发明公开了一种家用电器电源线外护套用聚醚砜/聚酰胺酰亚胺复合材料及其制备方法,其由以下质量份的原料制成:聚醚砜29~46份、聚酰胺酰亚胺22~37份、二羟基     

4,4′–二氟二苯甲酮的合成进展

介绍了一种重要的含氟精细化工产品和医药中间体4,4′–二氟二苯甲酮的理化性质、光谱性质及应用。综述了4,4′–二氟二苯甲酮国内外的合成研究情况,其合成方法主要包括Fridel–Crafts烷基化水解法、Fridel–Crafts酰基化法、卤素置换法、重氮化氧化法、催化羰基化法、4,4′–二氟二苯二氯乙烯氧化法、4,4′–二氟二苯甲烷氧化法等。     

Green Route for the Synthesis of Alanine-based Poly(amide-imide) Nanocomposites Reinforced with the Modified ZnO by Poly(vinyl alcohol) as a Biocompatible Coupling Agent

The objective of this article was fabrication and characterization of novel optically active poly(amide-imide)/zinc oxide nanocomposites with different modified ZnO nanoparticle contents under ultrasonic irradiation technique. For better dispersion of ZnO nanoparticles in a polymer matrix, their surface was modified with poly(vinyl alcohol) as a coupling agent. Effects of poly(vinyl alcohol) modifier on dispersity of nanoparticles, morphological structures, and thermal stability of the obtained nanoparticles were studied by several techniques. According to the transmission electron microscopy images of the nanocomposite, the average diameter of particles was around 7–15 nm in the poly(amide-imide).     

Thermally Stable and Optically Active Poly(amide-imide)s Derived from 4,4’–(Hexafluoroisopropylidene)-N,N’-bis-(phthaloyl-L-methionine) Diacid Chloride and Various Aromatic Diamines: Synthesis and Characterization

Summary Thermally stable and optically active poly(amide-imide)s (PAIs) have been synthesized and their properties such as optical activity, solubility, thermal stability were studied. Polymers were synthesized by solution polymerization of 4,4’–(hexafluoroisopropylidene)-N,N’-bis-(phthaloyl-L-methionine) diacid chloride and various aromatic diamines by three different methods. The compounds obtained were characterized by elemental C, H and N analysis, solubility, FTIR, ¹H NMR and ¹⁹F NMR spectroscopy. Thermogravimetric curves were also recorded. All data agree with the proposed structures.     

Nonlinear optical,poly(amide-imide)–clay nanocomposites comprising an azobenzene moiety synthesised via sequential self-repetitive reaction

Poly(N-acylurea)–clay nanocomposites consisting of a modified montmorillonite and poly(N-acylurea) were prepared from which poly(amide-imide)–clay nanocomposites were subsequently obtained via the sequential self-repetitive reaction of poly(N-acylurea). The moderate T_g of poly(N-acylurea) allows the nonlinear optically active polymer to exhibit high poling efficiency; in situ poling and curing increased the T_gs of poly(amide-imide)–clay nanocomposites. Electro-optical coefficients, r₃₃ of ～17–20 pm/V (830 nm), were achieved; high temporal stability (120 °C) and waveguide optical losses of 3.4–3.9 dB/cm at 1310 nm were also obtained for poly(amide-imide)–clay nanocomposites.     

Study of optically active methacrylates containing 1,1′‐binaphthyl side‐groups polymerized by anionic,group transfer and free radical methods

Optically active and racemic poly(meth)acrylates with pendant 1,1′‐binaphthalene moiety of 2‐methacryloyloxy‐ and 2‐acryloyloxy‐2′‐methoxy‐1,1′‐binaphthalene (MAMBN and AMBN) were synthesized by anionic, group transfer and free radical polymerization methods. Their polymerizability and chiroptical properties are somewhat different, depending on the three types of polymerization methods used. The yields for poly(MAMBN)s are lower than for poly(AMBN)s. The optical rotation of the optically active polymers is identical to that of the corresponding monomers. The values of specific rotation of optically active poly(AMBN)s are much larger than those of optically active poly(MAMBN)s. © 2002 Society of Chemical Industry     

Preparation and Characterization of New Optically Active Poly(amide imide)s Derived from N,N’-(4,4’-Sulphonediphthaloyl)-bis-(s)-(+)-valine Diacid Chloride and Aromatic Diamines under Microwave Irradiation

Summary The present paper is an extension of microwave method describing the synthesis of the new optically active poly(amide-imide)s. The main focus of this work is the design of new effective microwave method for preparing optically active poly(amide-imide)s. Imide-acid (3) was synthesized by the reaction of 3,3,4,4-diphenylsulfonetetracarboxylic dianhydride (1) with (s)-(+)-valine (2) in acetic acid. The compound 3 was coverted to diacid chloride 4 by reaction with excess amount of thionyl chloride. Polycondensetion reaction of diacid chloride 4 with several aromatic diamines such as 4,4-sulfonyldianiline (5a), 4,4-diaminodiphenyl methane (5b), 4,4-diaminodiphenylether (5c), p-phenylenediamine (5d), m-phenylenediamine (5e), 2,4-diaminotoluene (5f) and 4,4-diaminobiphenyl (5g) was carried out in the presence of small amount of o-cresol under microwave irradiation as well as conventional heating method. We obtained a series of optically active poly(amide-imide)s with high yield and inherent viscosity ranging from 0.22-0.35 dL/g. These new polymers were characterized by FT IR, ¹H NMR, elemental analyses and specific rotation techniques.     

Synthesis and characterization of new optically active poly(amide-imide)s containing 1,3,4-oxadiazole moiety in the main chain

Six new optically active poly(amide-imide)s were synthesized by poly condensation reaction of 2,5-bis(4-aminophenyl)-1,3,4-oxadiazole (8) with six chiral N,N′-(bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic)-bis-l-amino acids (3a–f) in a medium consisting of N-methyl-2-pyrrolidone (NMP), triphenylphosphite (TPP), calcium chloride (CaCl₂), and pyridine. Chiral N,N′-(bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic)-bis-l-amino acids (3a–f) were obtained by the reaction of bicyclo[2.2.2]-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (1) with two equimolar of l-alanine (2a), l-valine (2b), l-leucine (2c), l-isoleucine (2d), l-phenyl alanine (2e), and l-2-aminobutyric acid (2f) in acetic acid. The poly condensation reaction produced a series of novel poly(amide-imide)s (9a–f) in high yield and with inherent viscosities between 0.30 and 0.52 dL/g. The resulting polymers were characterized by elemental analysis, viscosity measurement, solubility testing, thermo-gravimetric analysis (TGA), ¹H-NMR, and FT-IR techniques.     

Sono-assisted Synthesis of MgAl-layered Double Hydroxide Nanosheet/multiwalled Carbon Nanotube Filler for the Fabricating of L-isoleucine Amino Acid Based Polymer Nanocomposites

Hybrid of acid functionalized multiwalled carbon nanotubes and layered double hydroxides were prepared by coprecipitation reaction of the Al(NO₃)_3·9H₂O, Mg(NO₃)_2·6H₂O, and acid functionalized multiwalled carbon nanotubes under ultrasonic irradiation. An optically active amino acid containing poly(amide-imide) was synthesized by the direct polycondensation reaction of the N,N′-(pyromellitoyl)-bis-L-isoleucine diacid and diamine using molten tetra-n-butylammonium bromide. These three-dimensional nanofillers were used as reinforcing agent to enhance the performance of chiral poly(amide-imide). The structure and morphology of the hybrid materials were confirmed by Fourier transformed infrared spectroscopy, X-ray diffraction, field emission and transmission electron microscopy, and thermogravimetry analysis techniques.     

Green Synthesis of Salicylic Acid-Based Poly(amide-imide) in Ionic Liquid and Composite Formation with Multiwalled Carbon Nanotube

A new salicylic acid-containing diacid monomer was synthesized by an established synthetic procedure from readily available reagents. The obtained diacid was used in the preparation of a thermally stable poly(amide-imide) by direct polycondensation with 4,4′-diphenylmethanediamine using 1,3-diisopropylimidazolium bromide ionic liquid as a green medium. The prepared polymer was used as matrix for preparation of multiwalled carbon nanotube/poly(amide-imide) composites in three multiwalled carbon nanotube concentrations (5, 10, and 15?wt%). The products were characterized for assessing the spectroscopic, thermal, and morphological properties by several methods. A homogeneous dispersion of multiwalled carbon nanotubes in the poly(amide-imide) matrix was observed by microscopy techniques.     

Synthesis and Properties of Novel Soluble and Thermally Stable Optically Active Poly(amide-imide)s from N,N’-(4,4’-Oxydiphthaloyl)-bis-L-phenylalanine Diacid Chloride and Aromatic Diamines

Summary In this research work, 4,4-oxydiphthalic anhydride (1) was reacted with L-phenylalanine (2) in acetic acid and the resulting imide-acid 3 was obtained in high yield. This imide-acid 3 was converted to diacid chloride 4 by reaction with thionyl chloride. The polycondensation reaction of diacid chloride 4 with several aromatic diamines such as 4,4-sulfonyldianiline (5a), 4,4-diaminodiphenyl methane (5b), 4,4-diaminodiphenylether (5c), p-phenylenediamine (5d), m-phenylenediamine (5e), and 4,4-diaminobiphenyl (5f) was performed by two conventional methods: low temperature solution polycondensation and short period reflux conditions. Several new thermally stable optically active poly(amide-imide)s with inherent viscosity ranging from 0.34–0.62 dL/g were obtained with high yield. All of the above polymers were fully characterized by ¹H-NMR, FT-IR, elemental analyses and specific rotation techniques. Some structural characterizations and physical properties of this new optically active poly (amide-imide)s are reported.     

Surface Treated Montmorillonite: Structural and Thermal Properties of Chiral Poly(Amide-Imide)/Organoclay Bionanocomposites Containing Natural Amino Acids

This work concerns the preparation of novel optically active nanocomposite materials derived from Cloisite Na⁺ clay, which has been functionalized by protonated l-methionine amino acid as a swelling agent for sufficient compatibilization with the poly(amide-imide) (PAI) matrix. The polymer chains were formed from the polycondensation reaction of N,N′-(pyromellitoyl)-bis-phenylalanine diacid chloride with 4,4′-diaminodiphenylether. Interaction between the two phases was established by modifying the PAI chains with amine end groups and free acid groups of the organoclay (OC). The effect of OC dispersion and the interaction between OC and PAI chains on the properties of resulting bionanocomposite material was studied using Fourier transform infrared spectroscopy, X-ray diffraction (XRD), transmission electron microscopy, field emission scanning electron microscopy and thermogravimetric analysis techniques. The XRD pattern and morphological investigation revealed the formation of intercalated and exfoliated OC platelets in the matrix. Because of the existence of naturally occurring amino acids as biological chiral resources, it is predictable that these materials may be potentially biodegradable and biocompatible.