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1.
AB2-type-prepolymerized monomer was rapidly (2 h) prepared at room temperature (25 ℃) using commercially available maleic anhydride (MA) and diethanolamine (DEA) as raw materials. By employing toluene-p-sulfonic acid as a catalyzer, a series of hyperbranched poly(amide-ester) (HBPAE) were successfully synthesized from prepared AB2 monomer by solution condensation polymerization through "one-step process" or "pseudo one-step process" (using pentaerythritol as a center core). The processes were carried out at high temperature of 120 ℃ for 6 h in air atmosphere (inert protection free) with reduced pressure distillation (0.08--0.096 MPa). The results of FT-IR, UV-Vis, TGA, and intrinsic viscosity testing by Ubbelodhe viscometer showed that the prepared HBPAEs possess three-dimensional configuration with unsaturated conjugate structure, large numbers of branches and numerous terminal hydroxyl groups. These result in their low viscosity, high solubility and thermal stability.  相似文献   

2.
JIN Xin  TANG  Li-Ming YOU  Hu 《结构化学》2010,29(7):1115-1121
<正>Three secondary amine terminated hyperbranched poly(ester-amine)s(defined as HPEA1,HPEA2 and HPEA3)were synthesized from piperazine(A_2)and trimethylolpropane triacrylate(TMPTA,B_3)at their molar ratios of 2.5:1,2.25:1 and 2.0:1,respectively.The polymers were analyzed by ~1H NMR,GPC,DSC and TGA.The results indicated that the ratio of secondary amine to tertiary amine and the content of secondary amine decreased,while the molecular weight, molecular weight distribution and glass transition temperature(T_g)increased from HPEA1 to HPEA3.Due to their reactive terminal groups and flexible chains,these polymers further reacted with an epoxy resin(E51)to form cured films under ambient conditions.With increasing the ratio between secondary amine groups and epoxy groups from 1:2 to 2:1,the gel content,film hardness and onset decomposing temperature of the cured samples increased.The good film performances should make the polymers as the components of non-solvent coating materials.  相似文献   

3.
Hydrophilic hyperbranched poly(ester-amine) (HPEA) synthesized from diethanolamine and methyl acrylate was used as phase transfer agent for the first time to transfer methyl orange(MO) from water into chloroform. This process was quantified by UV-Vis spectra. A possible mechanism was put forward based on the formation of amphiphilic aggregates.  相似文献   

4.
A series organosoluble and heterocyclic poly(ether-amide)s (PEA)s were synthesized from a new diamine containing pyridine moiety and four aliphatic-aromatic dicarboxylic acids by direct polycondensation reactions. Dicarboxilic acids 4a-4d containing ether groups were synthesized in two step reactions. At first, dialdehydes 3a-3d were synthesized from four dibromo alkanes la-ld and 4-hydroxybenzaldehyde 2, then dicarboxilic acids 4a-4d were synthesized from dialdehydes 3a-3d and malonic acid in a solvent free reaction. On the other hand, the new diamine 8 containing pyridine ring was synthesized in two step reactions. The structures of synthesized monomers and polymers were proven by FTIR, NMR spectroscopy and elemental analysis. Also all of the above polymers were fully characterized by inherent viscosity, solubility tests, gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The resulted PEAs have shown good inherent viscosities, solubility and thermal properties.  相似文献   

5.
Several iodohydrins are synthesized in fairly high yields by using polystyrene-supported phenyliodine(Ⅲ)bis(trifluoroacetate).  相似文献   

6.
张会良 《高分子科学》2014,32(7):914-922
In order to improve the flexibility of poly(propylene carbonate) (PPC), poly(1,2-propylene succinate) (PPSu) was used to plasticize PPC in a batch mixer. The effects of PPSu on the miscibility, thermal stability, mechanical and theological properties of the blends were investigated. PPC was partially miscible with PPSu. It was demonstrated that PPSu decreased the glass transition temperature and melt viscosity of PPC, as shown in the DSC and rheological curves. With the increase in PPSu content, the PPC/PPSu blends showed decreased tensile strength, however, the elongation at break was increased to 1100% for the 70/30 PPC/PPSu blend. The introduction of PPSu provided an efficient and novel plasticization method to extend the application area of PPC.  相似文献   

7.
柞蚕丝素蛋白与细胞具有特异性相互作用,作为生物医用材料具有潜在的研究和开发前景.凝胶是组织再生支架的重要材料形态之一,而迄今国内外尚无对柞蚕丝素蛋白凝胶化行为的系统性研究报道.本文研究了环境温度、pH值、柞蚕丝素溶液的浓度以及K^+、Ca^2+的浓度对再生柞蚕丝素蛋白的凝胶化速率的影响,研究了溶胶-凝胶转变过程中柞蚕丝素蛋白构象的变化.  相似文献   

8.
姚薇  贺爱华 《高分子科学》2014,32(5):633-639
Isotactic poly(butene-1) (iPB) with spherical morphology was synthesized successfully with bulk precipitation polymerization without post-treatment of the products. The bulk precipitation polymerization process made it possible for iPB to be used as general plastic due to the acceptable decreased cost compared with the solution polymerization process. The influence of catalyst residues on the aging and thermal stability of iPB synthesized by bulk precipitation polymerization method was investigated by gel permeation chromatography, mechanical performance testing, thermogravimetric analysis and infrared spectroscopic analysis. Commercial iPB and the lab-made iPB with varied catalyst residue contents were studied. The results demonstrated that the catalyst residues played an important role in the aging process of the iPB. A possible mechanism of aging promotion by catalyst residues was proposed.  相似文献   

9.
Recently, much attention has been paid to monodisperse, well-defined conjugated oligomers as candidates for molecular wires and molecular scale electronic devices. Shape persistent oligo ( 1,4-phenylene-ethynylene) s are especially attractive for their excellent main-chain rigidity and interesting electronic characteristics.  相似文献   

10.
陈枫  傅强 《高分子科学》2014,32(12):1724-1736
Inspired by the photoprotection, radical scavenging of melanin together with versatile adhesive ability of mussel proteins, polydopamine(PDA) nanoparticles were successfully prepared and incorporated into environmentally friendly polymer, poly(propylene carbonate)(PPC) via solvent blending. The prepared composites exhibited excellent thermal stability in air and nitrogen atmosphere and extraordinary mechanical properties. The composites displayed eminent increase of temperature at 5% weight loss(T5%) by 30-100 K with 0.3 wt%-2.0 wt% loadings, meanwhile, the tensile strength and Young's modulus were significantly improved from 11.5 MPa and 553.7 MPa to 40.5 MPa and 2411.2 MPa, respectively. The kinetic calculation indicated that improvement of T5% is presumably derived from suppressing chain-end unzipping. The glass transition temperature(Tg) of the PPC/PDA composites increased by 8-10 K. This is probably due to hydrogen bonding interaction since the abundant proton donors along PDA chains would interact with proton acceptors like C = O and C―O―C in PPC which would cause restriction of segmental motion of PPC chains.  相似文献   

11.
A series of non-isocyanate linear high molecular weight poly(ester urethane)s(PETUs)were prepared through an environmentallyfriendly route based on dimethyl carbonate,1,6-hexanediol and 1,6-hexanediamine.In this route,the polyurethane diol was first prepared by the reaction between bis-1,6-hexamethylencarbamate(BHC)and 1,6-hexanediol.A series of polyester soft segments of polyurethane have been synthesized from the polycondensation of adipic acid and different diols,including butanediol,hexanediol,octanediol and decanediol.The subsequent polycondensation of polyurethane diol and polyester diol led to linear PETUs.The resultant polymers were characterized by GPC,FTIR,1H-NMR,13C-NMR,DSC,WAXD,TGA and tensile test.The results indicated that PETUs possess weight-average molecular weights higher than 1×105 and the tensile strength as high as 10 MPa.The thermal properties,crystallization behavior,microphase separation behavior and morphology were studied by DSC and AFM,and the results indicated that the degree of phase separation was affected by two factors,the crystallization and hydrogen bonding interaction between soft segment and hard segment.  相似文献   

12.
以二聚甘油为原料,经过酯交换及氨基脱保护反应合成了一种两端含氨基的环状原酸酯新单体。该单体与辛二酸/十二烷二酸活性酯缩聚得到两种新的疏水性聚原酸酯共聚物POEAd-1和POEAd-2,其数均分子量分别由凝胶渗透色谱(GPC)测得为1.24×104及1.81×104,分散度(PDI)分别为1.59及1.93。热失重分析法证实POEAd-1和POEAd-2具有较高的热稳定性能,其起始降解温度分别可达198.5℃及202.5℃。溶血试验和MTT细胞毒性试验表明,POEAd-1和POEAd-2均具有良好生物相容性,作为一种潜在的生物医用材料,在药物缓控释领域将具有广阔的应用前景。  相似文献   

13.
A series of water soluble aliphatic hyperbranched poly(amido amine)s(PAMAMs) with the same or similar chemical structure of poly(amido amine) dendrimer was successfully synthesized from commercially available AB and Cn types of monomers by one-pot polymerization via the couple-monomer methodology(CMM). The AB type monomer used in this paper was methyl acrylate, and Cn monomers were multi-amino compounds such as ethylenediamine (EDA), diethylenetriamine (DETA), triethylenetetraamine (TETA). tetraethylenepentaamine (TEPA) and pentaethylenehexamine (PEHA). The reaction mechanism was investigated by means of the mass spectra of the reaction intermediates. Adjusting the feed ratio of AB to Cn. hyperbranched polymers with different terminal groups and properties were obtained. FTIR, NMR, DSC. and TGA were used to characterize the polymers. It was found that the polymers‘ properties such as solubility, thermal behaviour and encapsulation capability varied with changing the feed ratio of AB to Cn. Benzoyl and palmitoyl groups were introduced into these macromolecules by acidylation to form amphiphilic hyperbranched polymers which have a high capability to encapsulate water soluble dyes such as Congo red. It is expected that the hyperbranched PAMAMs can play an important role in the industrial applications, such as coatings, cross-linking and phase-transferring agents because of their versatility and availability.  相似文献   

14.
Summary: Novel hyperbranched poly(amine‐ester) (HPAE) cross‐linked films were prepared by cross‐linking the terminal hydroxyl groups of HPAE using glutaraldehyde (GA). Atom force microscope and scanning electron microscope revealed their smooth surfaces, dense and homogenous matrices. Property characterizations indicated that these cross‐linked films had good hydrophilicity, relative low protein adsorption, and high tensile strength. Also, their swelling behavior varied with the solvent.

Structure of the hyperbranched poly(amine‐ester).  相似文献   


15.
利用四甲基胍促进二羧酸与二溴代化合物的高效酯化聚合反应,设计、合成了一种新型手风琴式折叠链结构的聚酯脲.具有特殊结构的单体分别是4,4′-二羧基二苯基脲和3,5-二(溴代烷氧基)-苯甲酸酯,因此得到的聚酯脲具有类似接枝共聚物的结构.通过核磁氢谱(~1H-NMR)和傅里叶红外光谱(FTIR)对聚酯脲的结构及分子量进行了表征,结果显示,得到了分子量接近2×10~4的聚酯脲.通过核磁跟踪研究聚合反应动力学,结果表明,聚合反应速度与二溴单体的烷基链长度有关,二溴单体的烷基链较长时,聚合速率较慢.热重分析(TGA)结果显示,这种聚酯脲具有良好的热稳定性;由示差扫描量热(DSC)测试结果获知聚酯脲的熔融温度为57°C,表明它具有结晶性.脲基之间的氢键作用和苯环产生的π-π相互作用驱动这种聚酯脲在溶液中进行自组装.通过透射电子显微镜(TEM)研究聚酯脲的自组装行为,结果表明,该聚酯脲在氯仿和甲醇的混合有机溶剂中,静置4 h后,组装成片层结构;继续静置到3天后,形成了稳定的囊泡结构的聚集体,囊泡壁厚度约7 nm,接近折叠链宽度的预测值;小角X射线(XRD)测试结果表明聚酯脲是有序结构,进一步证实了合成的聚酯脲具有折叠链构象.  相似文献   

16.
A new naphthalene ring-containing bis(ester amine), 1,5-bis(4-aminobenzoyloxy)naphthalene (2), was synthesized from the condensation of 1,5-dihydroxynaphthalene with 4-nitrobenzoyl chloride followed by catalytic hydrogenation. A series of naphthalene-containing poly(ester amide)s having inherent viscosities of 0.34-0.82 dl/g were prepared by the direct phosphorylation polyamidation from bis(ester amine) 2 with various aromatic dicarboxylic acids. The poly(ester amide)s derived from terephthalic acid, 4,4′-biphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 4,4′-oxydibenzoic acid were semicrystalline and showed less solubility. The other polymers were amorphous and readily soluble in polar organic solvents and gave flexible and tough films via solution casting. Except for four examples, the poly(ester amide)s displayed discernible glass transitions between 190 and 227 °C by differential scanning calorimetry. These poly(ester amide)s did not show significant decomposition below 400 °C in nitrogen or air.  相似文献   

17.
通过己内酯和氨基己酸开环、缩合反应制备了酯段含量为81%的线性聚酯酰胺(PEA),并用熔融共混的方法制备了PEA/聚碳酸亚丙酯(PPC)共混物,考察了PEA的引入对共混体系相容性、热力学稳定性和机械性能的影响。 结果表明,PEA与PPC之间有较好的相容性,共混物的热力学稳定性比PPC有显著提高,当PEA质量分数为3%时,共混体系的起始分解温度(T-5%)和最大分解速率时的温度(Tmax)比PPC分别提高了52.7%和46.4%。 通过调节PEA的含量可以使共混体系同时达到增强和增韧的效果。  相似文献   

18.
High molecular weight aliphatic segmented poly(ether ester amide)s(PEEAs) were synthesized via melt polycondensation and chain extension. An oligomeric polyamide(PA) terminated mainly with -COOH groups(HOOC-PA-COOH) was prepared from the reaction of nylon 610 salt with sebacic acid. Melt polycondensation of HOOC-PA-COOH with polyethylene glycol(PEG), such as PEG400, PEG600, PEG1000 and PEG1500, was conducted at 200℃, and several segmented PEEA prepolymers(PrePEEAs) were prepared. Chain extension of PrePEEAs was carried out at 190℃ using 2,2'-(1,4-phenylene)-bis(2-oxazoline) and adipoyl biscaprolactamate as combination chain extenders. Chain extended PEEAs(ExtPEEAs) were characterized by gel permeation chromatography(GPC), Fourier transform infrared spectrophotometer(FTIR), proton nuclear magnetic resonance(1H NMR), differential scanning calorimetry(DSC), wide angle X-ray scattering(WAXS), thermogravimetry analysis(TGA), and tensile test. The ExtPEEAs exhibited Mn up to 98700, Tm from 164.2℃ to 176.1℃, initial decomposition temperature above 320.6℃, tensile strength up to 34.80 MPa, and strain at break from 111.92% to 353.12%. Aliphatic segmented PEEAs with good thermal and mechanical properties were prepared.  相似文献   

19.
以1,2,4-偏苯三羧酸酐(BTAA)和乙醇胺(EMA)为原料,分别采用"二步法"和"一步法"熔融缩聚制备了端羧基超支化聚酯酰胺(HBPEA).第1步利用官能团非等活性原理,在乙醇溶剂中由BTAA中高活性的酸酐基团与EMA中高活性的氨基反应原位生成含1个羟基和2个羧基的AB_2中间体,蒸除乙醇后,再第2步熔融缩聚得到超支化聚酯酰胺,可避免聚合过程中发生凝胶.为便于工业化应用,还采用BTAA与EMA经"一步"熔融缩聚制备了端羧基超支化聚酯酰胺.分别采用核磁共振(NMR)、乌氏黏度计、示差扫描量热仪(DSC)、热失重分析仪(TGA)以及阿贝折射仪等对2种方法所制备的目标产物化学结构和特性黏度等各项性能进行了表征,结果表明:所得聚酯酰胺具有超支化结构,特性黏数为0.12~0.15 d L/g,支化度为0.64~0.65,在350oC之前未发生热失重,玻璃化转变温度为125~126oC,折射率为1.57~1.58,与聚碳酸酯(PC)相近.因此将其作为加工助剂用于PC塑料体系的加工.超支化聚酯酰胺的加入,不仅能改善PC的加工流动性,同时还能改善制品的机械性能和表面光洁度,且不会引起PC色泽的变化.  相似文献   

20.
Summary: The reaction of hydrazine with ethyl glycolate results in 1,2‐bisglycoylhydrazine, a monomer that was used for the lipase‐catalyzed synthesis of biodegradable poly(ester hydrazide)s. The polymers derived from the hydrazide‐containing monomer and vinyl‐activated adipic, suberic, and sebacic acid, respectively, showed low melting temperatures of 136 to 141 °C and are thermally stable up to 300 °C. The aliphatic poly(ester hydrazide)s (PEHs) are highly crystalline, as proven by polarization microscopy and atomic force microscopy. Further, the PEHs represent the first described biodegradable poly(hydrazide)s. They degrade in the presence of lipase at 37 °C within a few weeks.

Synthetic route to poly(ester hydrazide)s.  相似文献   


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