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1.
Poly(ether amide) dendrimer segments based on 5-(2-aminoethoxy)-isophthalic acid have been synthesized using the convergent approach and mild reaction conditions. The monodendrons were combined to dendrimers via different core molecules and the resulting properties of the molecules were compared to those of the monodendrons. The melt polycondensation of the AB2 monomers with analog structure resulted first in undefined polymer structures. However, by thermal polyaddition reaction of suitable functionalized oxazoline monomers, well defined hyperbranched poly(ether amide)s with phenol terminal groups could be synthesized.  相似文献   

2.
In recent years, there have been concerted efforts to replace petrochemical products with those from renewable sources due to the unsustainability of petroleum feedstock, and the continued volatility in the price. This work describes the synthesis and thermal properties of two new lignin-derived poly(ether-amide)s as alternative thermoplastics to petroleum-based commodities. Poly-4-(2-aminoethoxy)benzoate (PEAB) and poly-4-(2-aminoethoxy)-3-methoxybenzoate (PEAV) are synthesized by a melt polycondensation and characterized by 1H NMR spectroscopy and thermal analysis. The number average molecular weight (Mn) of the polymers are estimated from the 1H NMR spectroscopy analysis, and were shown to be 4100 and 12,000 g/mol for PEAB and PEAV respectively. The PEAB had a higher decomposition temperature (Td) as well as glass transition temperature (Tg) compared to PEAV; albeit, with a lower molecular weight. The polymers’ Td were in the range of 330 °C–380 °C and the Tg were between 100 °C and 120 °C. The thermal properties of the polymers are in the desirable range for thermoplastic materials used in the packaging, storage, and coating industries. Furthermore, the polymers are susceptible to degradation under acidic conditions in a short period; a property that is highly desirable for degradable polymers. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2154–2160  相似文献   

3.
A new method to synthesize functionalizable branched poly(ethylene oxide) (PEO) is presented. Soluble linear poly(1,3‐diisopropenylbenzene) (1,3‐DIB) samples exhibiting one unsaturation per DIB unit in the chain were obtained through anionic polymerization. These unsaturations served, after reaction with a stoichiometric amount of cumyl‐potassium, as efficient initiators for the anionic polymerization of oxirane. Accurate characterization of these samples demonstrated that a far better control of the functionality is reached as compared to the case of poly(DVB) cores.  相似文献   

4.
The click reaction between azides and alkynes is been increasingly employed in the preparation of polymers. In this article, we describe the synthesis and click polyaddition reaction of a new A‐B‐type amide monomer—prepared from d ‐glucose as renewable resource—containing the alkyne and azide functions. Both Cu(I)‐catalyzed and metal‐free click polymerization methods were used to prepare glucose‐derived poly(amide triazole)s. The resulting polymers had weight‐average molecular weights in the 45,000–129,000 range and were characterized by GPC, IR, and NMR spectroscopies. Thermal and X‐ray diffraction studies revealed them to be amorphous. Their qualitative solubilities in various solvents and their water sorption have been studied. The poly(amide triazole)s having the alcohol functions protected as methyl ether were water‐soluble. The presence of the amide functions along the polymer chain made these polytriazoles degradable in the presence of sodium deuteroxide. The degradation was monitored by NMR analysis, and the degradation product was characterized by HRMS. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 629–638  相似文献   

5.
A diimide-diacid with oligoether spacer was synthesized from the condensation reaction of trimellitic anhydride with 1,8-diamino-3,6-dioxaoctane. Soluble poly(amide imide)s containing flexible groups were prepared through polycondensation reactions of diimide-diacid with different diamines via direct Yamazaki method. The poly(amide imide)s showed improved solubilty in polar aprotic solvents due to the presence of ether and alkyl flexible groups. According to the differential scanning calorimetry analysis, the glass transition temperatures of the polymers were in the range of 119-157 °C. According to thermogravimetric analysis, the temperatures for 10% weight losses were in the range of 348-387 °C that showed good thermal stabilities for these polymers.  相似文献   

6.
New diamino monomers IIa – IIg were synthesized in a two-step reaction sequence starting from p-acetamidobenzenesulfonyl chloride. Solution polymerization of these monomers in DMAC with terephthaloyl or isophthaloyl chloride resulted in the formation of a series of 14 poly(amide sulfonamide)s (PASAs) in excellent yield (> 95%). The polymers have in-trinsic viscosities of 0.32–1.11 dL g?1. Except for polymers IIIa ? p and IIId - p , all other PASAs were readily soluble in aprotic polar solvents including DMAC, DMF, and DMSO. Thermogravimetric analyses of the polymers showed moderate thermal stability with 10% weight loss being recorded in the range of 325–408°C. In addition, these polymers exhibit moderate chemical stabilities toward alkali, acidic, and chromic acid solution. © 1995 John Wiley & Sons, Inc.  相似文献   

7.
The influence of the molecular structure of five soluble poly(amide imide)s (PAI)s on their gas transport properties for carbon dioxide, oxygen, nitrogen, and methane has been studied. Permeabilities, diffusivities, and solubilities were determined by time lag measurements and correlated to chain packing and mobility as well as to polymer gas interaction. The PAIs were characterized by small‐ and wide‐angle X‐ray scattering. Molar masses and polymerization degrees were measured by light scattering. Additionally, glass transition temperatures, densities, and persistence lengths were determined. Pressure‐ and temperature‐dependent gas transport measurements have been done. It was found that the permeability is increasing with the diffusion coefficient which can be related to the fractional free volume. PAIs containing cardo diamines show higher diffusivities and permeabilities than poly(amide imide)s containing linear aromatic diamines due to higher fractional free volumes. The solubilities for PAIs containing the same imide compound correlate with the molar cohesive energy density. The exchange of hydrogen to fluorine atoms at one aromatic ring of the diamine increases the fractional free volume and cohesive energy density and, in consequence, the diffusion and solubility coefficient. Arrhenius behavior was observed for temperature dependence and decreasing permeability with increasing pressure. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 2183–2193, 1999  相似文献   

8.
Linear and branched poly(amide aspartimide)s were prepared through the reaction of 4,4′‐diaminodiphenylmethane with 4‐maleimidobenzoic acid and 5‐maleimidoisophthalic acid, respectively. The synthesis was performed through a one‐pot operation by means of the Michael addition reaction between amine and maleimide groups and the dehydration condensation reaction between amine and carboxylic acid groups. The obtained polymers exhibited fairly good solubility in aprotic polar solvents at room temperature and in pyridine, tetrahydrofuran, acetone, and chloroform upon heating. High glass‐transition temperatures (≥225 °C) and thermal stability above 360 °C were found for the polymers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1923–1929, 2005  相似文献   

9.
The synthesis of alkyl 2‐(carboethoxyhydroxymethyl)acrylates via the Bayllis‐Hillmann reaction pathway is described. These compounds are found to be poor monomers when involved in free radical polymerizations but present an extremely high reactivity upon Michael addition with primary amines leading to a simple, mild and efficient route to the preparation of new multifunctional heterocycles and polymers with potential applications in biodegradable coatings. Real‐time NMR spectroscopy permitted monitoring the extent of the reaction sequence and determining the conversion profile of reactants and Michael adduct intermediate. Poly(ester amide)s derived from diamine and hexane bis‐2‐(carboethoxyhydroxymethyl)acrylate were synthesized at room temperature by means of a very efficient Michael addition/cyclization polymerization. These polymers display excellent adhesion to metal, glass, and paper substrates and interesting hydrolytic susceptibility. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3182–3192, 2008  相似文献   

10.
The synthesis and characterization of a series of novel poly(aryl amide imide)s based on diphenyltrimellitic anhydride are described. The poly(aryl amide imide)s, having inherent viscosities of 0.39–1.43 dL/g in N-methyl-2-pyrrolidinone at 30°C, were prepared by polymerization with aromatic diamines in N,N-dimethylacetamide and subsequent chemical imidization. All the polymers were amorphous, readily soluble in aprotic polar solvents such as DMAC, NMP, dimethylsulfoxide, N,N-dimethylformamide, and m-cresol, and could be cast to form flexible and tough films. The glass transition temperatures were in the range of 284–366°C, and the temperatures for 5% weight loss in nitrogen were above 468°C. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4541–4545, 1999  相似文献   

11.
聚芳亚胺酰胺(PAIs)是一种新型高性能聚合物.本文作者讨论了卤素单体种类、溶剂、单体浓度、反应温度、催化体系及其添加量等工艺条件对PAIs相对分子质量和相对分子质量分布的影响,得到了钯催化C-N偶联缩聚反应制备高相对分子质量PAIs的最佳条件,为该类聚合物的进一步拓展和应用提供了参考.  相似文献   

12.
Journal of Thermal Analysis and Calorimetry - Random amino-alcohol-based poly(ester amide)s were synthesized using adipic acid and differently substituted amino-alcohols, namely 2-amino-ethan-1-ol,...  相似文献   

13.
14.
To obtain an understanding of the low molecular weight character of wholly aromatic poly(1,4-arylene acyldiamide oxime)s (PAAs) having n-alkyloxymethyl side braches and the additional decrease in molecular weight during their cyclodehydration reaction leading to the corresponding poly(1,4-arylene-1,2,4-oxadiazole)s (PAOs), tautomeric structures of poly[1,4-phenylene-2,5-bis(n-octyloxymethyl)terephthaldiamide oxime] (C8-PAA) were 1H-NMR-spectroscopically investigated by using two model compounds: O,O'-dibenzoyl terephthaldiamide oxime (H-PAA-M, 4) and O,O'-dibenzoyl-2,5-bis(n-octyloxymethyl) terephthaldiamide oxime (C8-PAA-M, 5). In solution H-PAA-M existed exclusively as oximino isomer, while C8-PAA-M consisted only of imino tautomer and C8-PAA contained both the oximino and imino form, the former being dominant in composition. It was found that the presence of imino tautomer caused serious effects both on the low molecular weight character of C8-PAA and on the additional decrease in molecular weight during thermal cyclodehydration to C8-PAO, whereas the presence of oximino tautomer showed practically little effect. A discussion on the results is provided from mechanistic viewpoint. © 1993 John Wiley & Sons, Inc.  相似文献   

15.
Poly(thioether amide)s containing pyridine moieties in their backbone were obtained by the polyaddition of 2,6-bis(acrylamido)pyridine (2,6-BAAP), derived from 2,6-diaminopyridine and acryloyl chloride, with an aromatic or aliphatic dithiol. The influence of various reaction conditions on the polyaddition was investigated in comparison with the polyaddition of 1,3-bis (acrylamido)benzene (1,3-BAAB). 2,6-BAAP gave the polymer even in the absence of any initiator at lower temperatures while 1,3-BAAB did not, which was attributable principally to intramolecular base catalysis of the pyridine moieties. Basic additives effectively promoted the reaction rate and increased the chain length. Those facts and NMR of the resulting polymers indicated Michael-type polyaddition. The polymers from 2,6-BAAP were amorphous and gave transparent and tough films having a high refractive index exceeding 1.7. GPC and DSC characterizations were also made. © 1993 John Wiley & Sons, Inc.  相似文献   

16.
程琳  蹇锡高 《中国化学》2000,18(3):414-417
Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[ 4-( 4-aminophenoxy) phenyl ]-(2H )-phtha-lazin-1-one and 1, 2-dihydro-2-( 4-aminophenyl )-4-[ 4-( 4-aminophenoxy) -3, 5-dimethylphenyl ] - (2H) -phthalazin-1-one were successfully synthesized using readily available heterocyclic bisphenol-like monomers through two steps in high yield. A series of novel poly( aryl ether amide)s containing the phthalazinone moiety with inherent viscosities of 1.16-1.67 dL/g were prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. The polymers were readily soluble in a variety of solvents such as N, N-dimethyl-formamide (DMF), N,N-dimethylacetamide (DMAc), dimethylsulfoxide ( DMSO ), N-methyl-2-pyrrolidinone (NMP), and pyridine. The polymers had high glass transition temperatures (Tg) in the 291-329℃ range.  相似文献   

17.
A series of main chain discotic liquid crystal polymers, synthesized following a new approach based on the incorporation of triphenylene units in both comonomers, show ordered columnar mesophases in a very wide thermal range, including room temperature. The introduction of branching points based on the same kind of triphenylene units increases their thermal range and gives rise to glassy low-temperature phases. Room temperature extrusion of these polymers yields fibers with molecules oriented perpendicular to the mechanical stress, and an orientational order parameter close to 0.5, which slightly increases for branched polymers.  相似文献   

18.
A new diamine containing ferrocene group with preformed ether and amide units was prepared via reaction of 1,1′-ferrocenedicarbonyl chloride with two moles of 2,6-bis(5-amino-1-naphthoxy)pyridine. Polycondensation reactions of the prepared diamine with different aromatic and aliphatic diacid chlorides in the presence of trimethylchlorosilane (TMSCl) resulted in preparation of novel ferrocene modified poly(amide ether amide)s. The monomer and polyamides were characterized and the effect of trimethylchlorosilane (TMSCl) as activating agent on the polymerization reaction was studied. The physical and thermal properties of the polyamides including inherent viscosity, solubility, thermal stability and behavior, flame-retardancy and crystallinity of the polymers were studied. The polymers showed good thermal stability and flame-retardancy, and also improved solubility in polar aprotic solvents.  相似文献   

19.
A series of new poly(amide imide)s was prepared from new diacid containing sulfone, ether, amide and imide groups with various aromatic diamines. The diacid was synthesized via four steps, starting from reaction of 4-aminophenol with 4-nitrobenzoyl chloride in the presence of propylene oxide afforded N-(4-hydroxy phenyl)-4-nitrobenzamide. In the second step, reduction of nitro group resulted in preparation of 4-amino-N-(4-hydroxy phenyl) benzamide. In the next step for the preparation of diamine, the reaction of 4-amino-N-(4-hydroxy phenyl) benzamide with bis-(4-chlorophenyl) sulfone in the presence of K2CO3 was achieved. The prepared sulfone ether amide diamine was reacted with two moles of trimellitic anhydride to synthesize related sulfone ether amide imide diacid. The precursors and final monomer were characterized by FT-IR, H-NMR and elemental analysis. Direct polycondensation reaction of the sulfone ether amide imide diacid with different diamines in the presence of triphenyl phosphite afforded five different poly (sulfone ether amide imide amide)s. The obtained polymers were fully characterized and their physical properties including thermal behavior, thermal stability, solubility, and inherent viscosity were studied.  相似文献   

20.
A series of novel biodegradable unsaturated poly(ester amide)s (UPEAs) were synthesized through the solution polycondensation of two unsaturated monomers, di‐p‐nitrophenyl fumarate and L ‐phenylalanine 2‐butene‐1,4‐diol diester p‐toluene sulfonate, and four other saturated monomers in different combinations. The UPEAs were obtained in fairly good yields with N,N‐dimethylacetamide (DMA) as the solvent. The number‐average and weight‐average molecular weights of the UPEAs, measured by gel permeation chromatography, ranged from 10 to 30 kg/mol, they had a rather narrow molecular weight distribution of 1.40. The chemical structures of the novel biodegradable UPEAs were confirmed by both IR and NMR spectra. The UPEAs had higher glass‐transition temperatures than saturated PEAs of similar structures, and their glass‐transition temperatures were affected more by the CC double bond located in the diamide part than by those in the diester part. The solubility of the polymers was poor in water but better in DMA and dimethyl sulfoxide. With the availability of these inherent CC double bonds in the UPEA backbones, these UPEAs have the functionality of CC bonds, such as photochemical reactivity or the ability to react with or be modified by other bioactive or other environmentally sensitive compounds, and this can easily extend their applications to biomedical and pharmaceutical areas. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1463–1477, 2005  相似文献   

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