Preparation and properties of poly(amideether-imide)s derived from 1,4-bis(4-aminophenoxy)benzene,trimellitic anhydride,and various aromatic diamines

An imide ring containing dicarboxylic acid, 1,4-bis(4-trimellitimidophenoxy)benzene (III), was prepared by the condensation of 1,4-bis(4-aminophenoxy)benzene and trimellitic anhydride. A series of new poly(amide-ether-imide)s were prepared by the direct polycondensation of diimide-diacid III with various aromatic diamines using triphenyl phosphite and pyridine as condensing agents inN-methyl-2-pyrrolidone (NMP) in the presence of calcium chloride. The highest inherent viscosity value of a poly(amide-ether-imide) obtained was 1.78 dL/g (inN,N-dimethylacetamide, DMAc, at 30 °C). Flexible films with excellent tensile properties were cast from DMAc solutions. Glass transition temperatures of these poly(amide-ether-imide)s were recorded in the range of 248–297 C. These polymers do not show obvious weight loss before 400°C; the decomposition temperatures at which 10% weight loss in nitrogen and in air were observed for these poly(amide-ether-imide)s in the range of 521–564°C and 501–539°C, respectively. The polymers derived fromp-phenylenediamine or the diamines containing 1,4-bisphenoxy units exhibited a higher degree of crystallinity and higher initial decomposition temperatures but poor solubility in organic solvents.     

1,3-双(4-氨基苯氧基)苯的合成方法研究

间苯二酚和对氯硝基苯经缩合反应、合成得到1,3-双(4-硝基苯氧基)苯,以FeCl3.6H2O/C为催化剂,水合肼为还原剂,在乙醇中还原得到1,3-双(4-氨基苯氧基)苯。采用薄层色谱(TLC)对反应进程进行了跟踪研究,并用熔点测定仪、DSC,FT-IR、1H-NMR和元素分析等分析方法对目标产物的结构进行了表征。试验结果表明:当m[1,3-双(4-硝基苯氧基)苯]=14.1 g(40.1 mmol)、V(水合肼)=20 mL时,选择催化剂m(FeCl3.6H2O)=1.00 g、m(C)=2.50 g进行反应,并控制水合肼加入时的反应温度为70℃,加完以后在回流温度进行反应,还原反应产物的得率可达60%左右[以1,3-双(4-硝基苯氧基)苯计]。     

Synthesis and Properties of Novel Fluorinated Poly(amide-imide)s from the 4,4′-Bis(4-trimellitimido-2-trifluoromethylphenoxy)biphenyl and Aromatic Diamines

A novel fluorinated diimide dicarboxylic acid, 4,4′-bis(4-trimellitimido-2-trifluoromethylphenoxy)biphenyl (III), was synthesized from the condensation of 4,4′-bis(4-amino-2-trifluoromethylphenoxy)biphenyl (I) and trimellititc anhydride. A series of soluble poly(amide-imide)s (PAI) V_a–h having inherent viscosities of 0.56–0.97 dL/g were prepared from reacting III with an equivalent amount of diamines by direct polycondensation using triphenyl phosphite and pyridine as condensing agents. The polymer V series afforded tough, transparent, and flexible films. They had tensile strengths ranging from 88 to 112 MPa, elongations at break from 8 to 31%, and initial moduli from 1.9 to 2.7 GPa. The glass-transition temperature (T_g) of the polymers was recorded at 235–300^○C. They had 10% weight loss at a temperature above 502^○C and left more than 54% residue even at 800^○C in nitrogen. In comparison with the nonfluorinated PAI VI series, the fluorinated V exhibited better solubility.     

1，4-双（4-氨基苯氧基）-2，5-二特丁基苯及其聚酰亚胺的合成与性能研究

在有机溶剂体系中,2,5-二特丁基对苯二酚与对氯硝基苯在碳酸钾的作用下进行缩合反应,得到了1,4-双（4-硝基苯氧基）-2,5-二特丁基苯晶体（14BNPODTB）,随后,在钯/碳-水合肼的还原体系中反应,获得了高纯度的白色1,4-双（4-氨基苯氧基）-2,5-二特丁基苯（14BAPODTB）晶体产物。利用差示扫描量热计（DSC）,熔点仪,傅立叶转换红外光谱仪（FTIR）等分别对其进行了表征。另外,也进行了聚合试验,获得了聚酰胺酸树脂（14BAPODTB-440DA／PMDA—PAA）溶液,涂膜,热亚胺化,制得了聚酰亚胺薄膜（14BAPODTB-440DA／PMDA—PI）,并对其性能进行了研究。     

Synthesis of new poly(amide-imide)s XX. Preparation and properties of poly(amide-Imide)s derived from 1,7-Bis(4-aminophenoxy) naphthalene,trimellitic anhydride,and various aromatic diamines

A dicarboxylic acid (1,7-BTMPN) bearing two preformed imide rings, was prepared from the condensation of 1,7-bis(4-aminophenoxy)naphthalene and trimellitic anhydride. A new family of poly(amide-imide)s with inherent viscosities up to 1.56 dL/g (0.5g/dL in DMAc at 30 °C) was prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid 1,7-BTMPN with various aromatic diamines in a medium consisting ofN-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers were readily soluble in polar solvents such as NMP and DMAc. All the soluble poly(amide-imide)s can form transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 185–267°C and the 10% weight loss temperatures were above 430 °C in nitrogen.     

Synthesis and characterization of adamantane-containing poly(enaminonitriles)

The first aliphatic bis(chlorovinylidene cyanide) monomer, 1,3-bis(1-chloro-2,2-dicyanovinyl)adamantane, has been synthesized and polymerized with appropriate diamines to give adamantane-containing aromatic-aliphatic and all aliphatic poly(enaminonitriles) (PEANs) via vinylic nucleophilic substitution polymerization. The PEANs showed excellent solubility in polar aprotic solvents and good thermal stability (10% weight loss in air > 320 °C), despite the aliphatic contents of the polymers. Solution inherent viscosities of 0.23-0.90 dL/g were obtained.Three other new PEANs containing the adamantane-based cardo group were also synthesized via vinylic nucleophilic substitution polymerization from the adamanaine-containing cardo diamine 2,2-bis[4-(4-aminophenoxy)phenyl]adamantane. The cardo PEANs showed better solubility in common organic solvents than the corresponding cardo polyamides. They also showed good thermal stabilities (10% weight loss in air > 339 °C) comparable to those of the corresponding cardo polyamides.     

新型含氟聚醚酰亚胺的合成与表征

利用对苯二酚、2-氯-5-硝基三氟甲苯合成得到1,4-双(2-三氟甲基-4-硝基苯氧基)苯,再在钯/炭、水合肼和有机溶剂的作用下,合成得到了1,4-双(2-三氟甲基-4-氨基苯氧基)苯,并对其性能进行了表征,包括其本身的熔点、红外吸收特征等。合成得到的1,4-双(2-三氟甲基-4-氨基苯氧基)苯与4,4'-二氨基二苯醚、2,2-双[4-(3,4-二羧基苯氧基)苯基]丙烷二酐反应,制得了含氟聚醚酰亚胺,并对其性能进行了表征。     

新型高分子材料——聚亚胺酮的合成与性能研究

通过傅-克酰基化反应合成了1,4-双-(4′-溴苯酰基)苯。以1,4-双-(4′-溴苯酰基)苯和芳香二胺为单体,通过钯催化的胺基化反应缩聚合成了新型高性能聚合物——聚亚胺酮(PIKs)。其结构由红外和核磁氢谱表征,表征结果与目标结构吻合良好。通过差示扫描量热仪(DSC)和热重分析(TG)等对PIKs的主要性能进行了测定,研究表明:该系聚合物有较高的玻璃化转变温度(Tg>230℃)、良好的热稳定性(高的热分解温度TD>500℃)及优秀的的溶解性能,其中PIK-3在室温下(20℃)可溶解在普通有机溶剂三氯甲烷(CHCl3)中。     

Synthesis, characterization and thermal properties of soluble aromatic poly(amide imide)s

Novel diamines such as N,N′-bis(aminoaryl)terephthalamido-2-carboxylic acids (BATCA), which contain primary amine, amide and carboxylic acid groups and are soluble in dilute aqueous NaOH solution, were synthesized by reacting aromatic diamines with trimellitic anhydride chloride in dimethylformamide. Poly(amide imide)s containing 3:1 ratio of amide:imide groups in the polymer chain were prepared by low temperature solution polymerization of BATCAs with isophthaloyl chloride or terephthaloyl chloride in dimethylformamide at 5-10 °C to form poly(amide amic acid)s, and followed by treating with a mixture of triethylamine and acetic anhydride. The PAIs were soluble in polar aprotic solvents like dimethylformamide, dimethylacetamide, dimethylsulphoxide and N-methylpyrrolidone, and have inherent viscosities in the range of 0.30-0.66 dL/g. The PAIs were characterized by IR, ¹H NMR and ¹³C NMR techniques. Thermogravimetric analysis (TGA) has shown that the initial decomposition temperatures of the polymers are in the range of 250-440 °C, depending upon the structures of diamine and diacid chloride. The glass transition temperatures of the PAIs are in the range of 128-320 °C. The IDT and T_g values of the polymers containing terephthaloyl unit are higher by about 20-40 °C than those of the polymers with isophthaloyl unit. BATCA could be utilized for the preparation of thin film composite membranes having PAA/PAI barrier layer on PES by in situ interfacial polymerization with IPC/TPC/TMC.     

Synthesis of new aza thia crowns under microwave irradiation

Some new aza thia crowns were prepared. A new diester was first prepared from the reaction of α,α′-bis(bromomethyl) benzene and methylthioglycolate. Aza crowns were synthesized from the reactions of this diester and diamines (ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, and diethylenetriamine) in refluxing methanol (conventional heating) and under microwave (MW) irradiation. Based on the yields of aza crowns under these two conditions, MW irradiation is the better medium for these syntheses.     

对苯二甲基二甲醚的制备

以对二氯苄为原料,与甲醇钠反应合成了对苯二甲基二甲醚,对其工业化生产工艺进行了优化。     

Effect of structure of aromatic diamines on curing characteristics,thermal stability,and mechanical properties of epoxy resins. I

The curing behavior of diglycidyl ether of bisphenol-A (DGEBA) with aromatic diamines having aryl–ether, aryl–ether–carbonyl, and aryl–ether–sulfone linkages was studied using differential scanning calorimetry (DSC). Aromatic diaminessuch as 1,3-bis(aminophenoxy)benzene (R), 1,4-bis(aminophenoxy)benzene (H),2,2′-bis[4-(4-aminophenoxy)phenyl]propane (B), 4,4′-bis(4-aminophenoxy)benzo-phenone (P), and bis[4-(4-aminophenoxy)phenyl]sulfone (S) were synthesized and characterized in the laboratory. Curing of DGEBA was done using both stoichiometric and nonstoichiometric amounts of diamines and the reaction was monitored using DSC. The reactivity of the diamines depended on the structure. The presence of electron withdrawing groups, even though significantly apart from the reaction site, reduced the nucleophilicity. No significant change was observed in the activation energy for curing, which was around 56 ± 2 kJ/mol. The glass transition temperature of the epoxy network depended on the structure and was higher when diamines P and S were used in comparison to diamines R, H, and B. The cured resins were stable up to 300°C, and maximum char yield (i.e., 32% at 600°C) was obtained in DGEBA cured with diamine P. The room temperature mechanical properties only changed marginally with the structure of the diamines. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1759–1766, 1998     

Layered zinc 4-phosphonoisophthalates pillared by flexible bis(imidazole) Co-ligands

This paper reports two zinc phosphonates based on 4-phosphonoisophthalic acid (4-piH₄) and bis(imidazole) co-ligands, namely, [Zn₂(4-pi)(1,2-bix)] (1) and [Zn₂(4-pi)(1,3-bix)] (2) (1,2-bix = 1,2-bis(imidazol-1-ylmethyl)benzene, 1,3-bix = 1,3-bis(imidazol-1-ylmethyl)benzene). Both show layer structures in which the inorganic tetranuclear cores of Zn₄P₂O₆ are connected by 4-pi⁴⁻ligands. The 1,2-bix or 1,3-bix ligand binds to the Zn atoms within the tetranuclear unit or between the neighboring tetranuclear units in a cis-coordination mode, and fill in the interlayer spaces in both cases. The luminescent properties are investigated.     

Synthesis and Characterization of processable heat resistant poly (amide-imides) for high temperature applications

Summary A series of new polyamide-imides with high thermal stability were synthesized by direct polycondensation of imide containing diamines with various aromatic diacids using polar aprotic solvents. In this technique triphenylphosphite (TPP) and pyridine were used as condensing agents to form polyamide-imide through N-phosphonium salts of pyridine. The various imide containing diamines were prepared by reacting dianhydride (PMDA, BPTDA) with aromatic diamines such as phenylene diamine, 3,3’-dichloro 4,4’-diaminodiphenylmethane and 2,6-diaminopyridine in 1:2 ratio. The diacids containing flexible ether units were prepared by treating diol with aromatic acid (2,4-dichlorobenzoic acid). The polyamide-imides obtained by this technique were characterized by elemental analysis, FTIR and ¹H-NMR. The solubility of these polyamide-imides was found to be good in polar aprotic solvents such as NMP, DMF, and DMAc etc. The viscosity of the polyamide-imides were determined and found to be in the range of 1.21 to 1.76 dl/g indicating the formation of high molecular weight polymers. The thermal stability of the polymers was tested using DSC and the Tg values are in the range of 207–234 °C showing the high thermal stability of the prepared polymers.     

1,4-二[2-(3-氨基苯甲酰)乙烯基]苯的合成

以对苯二甲醛、间氨基苯乙酮为原料经羟醛缩合反应合成了光敏性二胺:1,4 二[2 (3 氨基苯甲酰)乙烯基]苯(Ⅰ)。通过优化实验得到最佳的合成工艺为:对苯二甲醛、间氨基苯乙酮在0℃,以乙醇为溶剂,氢氧化钠为催化剂,进行羟醛缩合反应3h,产物经重结晶提纯。Ⅰ收率为86 4%,w(Ⅰ)=99 91%。并用元素分析、红外光谱对Ⅰ的结构进行了表征。     

Organosoluble and Light-colored Fluorinated Polyimides from 2,2-Bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]sulfone and Aromatic Dianhydrides

A new trifluoromethyl-substituted diamine monomer, 2,2-bis[4-(4-amino-2-trifluoromethylpenoxy)phenyl]sulfone (II), was prepared through the nucleophilic substitution reaction of 2-chloro-5-nitrobenzotrifluoride and 4,4’-sulfonyl diphenol in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd/C. Novel fluorinated polyimides V_a–f having inherent viscosities ranging from 0.74 to 1.14 dL/g were synthesized from the diamine II with various aromatic dianhydrides via thermal imidization of poly(amic acid). Most of V series were soluble in the all test solvents, except V_b(H). These polyimide films had strengths at yield of 94–119 MPa, tensile strengths of 90–118 MPa, elongations to break of 10–16%, and initial moduli of 2.0–2.4 GPa. The glass transition temperature (T_g) of these polymers were in the range of 244–297 ^○C, their 10% weight loss temperatures were above 520 ^○C under ether nitrogen or air atmosphere, and left more than 45 wt% residue even at 800 ^○C in nitrogen. Compared with polyimides VII based on 4,4’-bis(3-aminophenoxy)diphenyl sulfone (II’), V showed better solubility and lower color intensity, dielectric constant, and moisture absorption. Their films had cutoff wavelengths between 355–402 nm, b^* values ranging from 6.8 to 32.9, dielectric constants of 3.32–4.27 (1 MHz), and moisture absorptions in the range of 0.27–0.62 wt%.     

Reactions of 2,4-diaryl 1,3,2,4-dithiadiphosphetane-2,4- disulfides with disilylated resorcinols

Bis(trimethylsilyl) esters of bisaryldithiophosphonic acids were obtained in 70–81% yields by the reactions of 2,4-diaryl 1,3,2,4-dithiadiphospheta ne-2,4-disulfides with 1,3-bis(trimethylsilyloxy)benzene and 2-methyl 1,3-bis(trimethylsilyloxy)benzene.     

Synthesis and characterization of novel aromatic poly(benzimidazole-amide)/Ag and Cu nanocomposites through transition metal complexation

A new thermally stable aromatic poly(benzimidazole-amide)s PBIAs was synthesized by low-temperature polycondensation of bis-benzimidazole diamines; 1,4-bis(5-amino-1H-benzimidazol-2-yl)benzene (3a) and 1,3-bis(5-amino-1H-benzimidazol-2-yl)benzene (3b) with two different diacid chlorides. Diamines 3a and 3b were prepared via direct condensation of 1,2-phenylene diamine and terephthalic or isophthalic acid in polyphosphoric acid in high yield. Chemical structures of synthesized monomers were confirmed by elemental analyses and spectroscopic methods. The structures of synthetized polymers were confirmed by FT-IR, ¹H-NMR, elemental and thermogravimetric analysis (TGA), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Thermal stability of the polymers was ascertained via 10 % weight loss temperatures in the range of 315–380 °C (inert atmosphere). Existence of benzimidazole moieties in polymer’s structure makes them suitable for easy coordination to Lewis acids or metallic ions, whereas the substitution of C–H or N–H protons allows for the synthesis of complex derivatives. As a result, a series of novel nanocomposites, via metal complexation of PBIA6a due to their great solubility with Ag⁺ or Cu²⁺ cations followed by reduction to metals by sodium borohydride (NaBH₄), was prepared. The resulting nanocomposites’ structures were confirmed by FT-IR, XRD, TGA, UV/vis, FE-SEM, TEM and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM–EDX). The FE-SEM, TEM and SEM–EDX results indicated that Cu and Ag particles were dispersed homogenously in nano scale in the polymer matrix.     

Polyimides based on “multiring” flexible diamines

The five benzene rings-containing (hereafter for convenience, referred to as five-ringrd) diamines ad-bis[4-(4-aminophenoxy)phenyl]-1,4 (or 1,3)-diisopropylbenzene (p- or m-3) were prepared by a nucleophilic substitution of ,-bis(4-hydroxyphenyl)-1, 4 (or 1,3)-diisopropylbenzene (p- or m-1) with p-chloronitrobenzene in the presence of K₂CO₃ and then hydro-reduced. The polyimides were synthesized from diamine 3 and various aromatic dianhydrides via the two-stage procedure that include ring-opening polyaddition in DMAc to give poly(amic acid)s, followed by thermal conversion to polyimides. The poly(amic acid)s had inherent viscosities of 0.63–1.54 dL/g depending on the dianhydrides used. Almost all the poly(amic acid)s could be solution-cast and thermally converted into transparent, flexible, and tough polyimide films. These polyimides have glass transition temperatures in the range of 186–290°C and almost no weight loss up to 500°C in air or nitrogen atmosphere. The polyimide obtained from pyromellitic dianhydride and diamine m-3 showed two endothermic peaks of 270 and 300°C on the diagram of differential scanning calorimetry (DSC), and the other polyimides showed no endotherms on their DSC traces.     

Modified poly(ether–imide–amide)s with pendent benzazole structures: Synthesis and characterization

Three series of novel modified poly(ether–imide–amide)s (PEIAs) having pendent benzazole units were prepared from diimide–dicarboxylic acids, including 2-[3,5-bis(4-trimellitimidophenoxy) phenyl]benzimidazole, 2-[3,5-bis(4-trimellitimidophenoxy) phenyl]benzoxazole, and 2-[3,5-bis(4-trimellitimidophenoxy) phenyl]benzothiazole, with various diamines by direct polycondensation in N-methyl-2-pyrrolidone with triphenyl phosphite and pyridine as condensing agents. These new diimide–dicarboxylic acids containing ether linkages and benzazole pendent groups were synthesized by the condensation reaction of 5-(2-benzimidazole)-1,3-bis(4-aminophenoxy)benzene, 5-(2-benzoxazole)-1,3-bis(4-aminophenoxy)benzene, or 5-(2-benzothiazole)-1,3-bis(4-aminophenoxy)benzene with trimellitic anhydride, respectively. All of the polymers were obtained in quantitative yields with inherent viscosities of 0.39–0.65 dL/g. For comparative purposes, the corresponding unsubstituted PEIAs were also prepared by the reaction of a diimide–dicarboxylic acid monomer lacking benzazole pendent groups, namely, 3,5-bis(4-trimellitimidophenoxy) phenyl, with the same diamines under similar conditions. The solubilities of the modified PEIAs in common organic solvents and their thermal stability were enhanced compared to those of the corresponding unmodified PEIAs. The glass-transition temperature, 10% weight loss temperature, and char yields at 800°C were 19–31°C, 22–57°C and 4–8% higher, respectively, than those of the unmodified polymers. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012