一种新型热致性液晶聚酯酰亚胺的合成与表征

在Higashi直接缩聚法的基础上,利用分步投料法,以N,N-己二撑-1,6-双苯偏三酸酰亚胺二胺(IA6)、对羟基苯甲酸(PHB)和对苯二酚二对羟基苯甲酸酯(PHQ)为主要原料,合成了一种新型三元共聚液晶聚酯酰亚胺(IA6PP)。采用FTIR、DSC、TGA、POM和WAXD等方法研究了单体种类对所合成的聚合物结构和性能的影响。结果表明:IA6PP呈现出典型的向列型液晶的特征,液晶温度区间为252~365℃,热稳定性明显高于由4,4-二羟基二苯甲酮(DHBP)、IA6和PHB合成的液晶聚酯酰亚胺(IA6PD)。     

膜用聚酯母粒热性能研究

通过DSC、TG研究了膜用聚酯母粒的热性能，分析了DSC潜回上熔体冷却结晶峰、冷结晶峰等热谱特征与工艺适应性的关系．结果表明，熔作冷却结晶峰宽而矮，峰点温度较低，结晶速度较慢的聚酯母位，其拉膜工艺适应性较强；反之则工艺适应性较差。     

基于聚3-叠氮甲基-3'-甲基环氧丁烷的三唑交联弹性体的制备及其热性能研究

针对叠氮粘合剂与异氰酸酯的固化反应易受到水分的影响,且与高能氧化剂二硝酰胺铵(ADN)相容性差的问题,制备了低熔点的双炔固化剂环己烷二甲酸丙炔醇酯(BPHA),并与叠氮粘合剂PAMMO通过点击化学反应制备了三唑交联弹性体,采用红外光谱对比研究了交联反应前后特征官能团的变化,通过平衡溶胀法研究了所制备弹性体的交联密度,采用TG-MS联用技术分析了弹性体分解的气体产物。结果表明,基于PAMMO的三唑交联弹性体的经历两阶段受热分解过程,第一阶段主要发生叠氮侧基的裂解释放出N_2,第二阶段的气相分解产物为CO_2、CH_2O、HCN、H_2O及N_2。     

双交联单体改性PVAc乳液胶粘剂的合成及性能研究

以邻苯二甲酸二烯丙酯(DAP)为预交联单体,以乙烯基三乙氧基硅烷(VTES)为后交联单体,采用半连续种子乳液聚合法制备了双交联单体改性的聚醋酸乙烯酯(PVAc)乳液。研究了两种单体使用量对乳液聚合稳定性的影响,并通过多种手段对所得乳液进行性能表征。研究结果表明：当VTES与DAP的质量分数分别为4%和2.5%时,聚合反应可稳定进行;改性乳液胶膜的吸水率最低至8.3%,静态接触角最大为80.2°,与木材粘接的湿剪切强度最高可达2.53 MPa,乳液胶膜的玻璃化转变温度(T_g)达到28.76℃,初始分解温度达到307.78℃,表明此双交联单体改性的PVAc乳液的耐水性、热稳定性均得到了大幅提高。     

热致性液晶全芳共聚酯的设计合成及其性能研究

通过熔融酯交换法,合成了一系列五元全芳共聚酯。利用热台偏光显微镜(PLM)、示差扫描量热法(DSC)等测试分析手段对所合成的产物进行了表征。研究发现,二羟基二苯酮在二酚单体中相对含量较高的情况时聚合产物具有较好的液晶性和成纤性能,表明该单体有利于合成高成纤性、高强度和低熔融加工温度的全芳液晶共聚酯。     

热致性液晶聚酯的合成及与环氧树脂共混物的性能研究

通过溶液缩聚法合成了热致性液晶聚酯(PHDT)，并用差热分析、红外光谱及偏光显微镜等方法对其结构和性能进行了表征，然后将其与环氧树脂共混，制得了热致性液晶聚酯/环氧树脂共混物。研究发现，加入5％的PHDT，可使共混物的冲击强度、弯曲强度及玻璃化转变温度分别增加80．1％、20．5％和15℃。利用SEM观察了其断裂形貌，并探讨了其增韧机理。     

聚乙二醇对阳离子染料易染聚酯热性能的影响

采用1L聚合釜装置合成了含有第三单体——间苯二甲酸乙二酯-5-磺酸钠(SIPE)及不同质量分数的第四单体——聚乙二醇(PEG)的一系列阳离子染料易染聚对苯二甲酸乙二酯(ECDP),并对其化学结构进行表征.利用差示扫描量热仪(DSC)、热重分析仪(TGA)、接触角测试仪对合成的ECDP的热性能及亲水性进行了研究.结果表明:随着PEG质量分数的增加,ECDP的玻璃化转变温度、熔点和热分解温度均相应下降,热稳定性减弱,但亲水性有不同程度的提高.     

一种巯基酯类光敏胶单体的合成及其性能研究

以三羟甲基丙烷(TMP)、3-巯基丙酸为主要原料,采用酯化反应法合成了一种重要的巯基酯类光敏性单体TMPMP[三羟甲基丙烷三(3-巯基丙酸酯)]。通过单因素试验法优选出合成TMPMP的最佳工艺条件,并采用红外光谱(FT-IR)法、核磁共振氢谱(1H-NMR)法和元素分析法等对TMPMP结构进行了表征。结果表明:当m(TMP)=6.71 g、m(3-巯基丙酸)=19.10 g、m(催化剂对甲苯磺酸)=0.59 g、V(携水剂甲苯)=40 mL和反应时间为1.5 h时,产物酯化率为98.6%,收率为79.6%;以TMPMP作为UV固化胶的光敏性单体,以三羟甲基丙烷三丙烯酸酯(TMPTA)为主要原料,制成的巯基/烯烃UV固化胶具有良好的固化性能及耐热性能,满足光学领域的应用要求。     

Fabricating novel thermal crosslinked ultrafine fibers via electrospinning

In this article, we report the preparation of a kind of novel crosslinked ultrafine fiber by electrospinning of unsaturated polyester macromonomers (UPM) and subsequent thermal crosslinking. The UPM is prepared via a two‐step reaction with poly(2‐methyl‐1,3‐propyleneadipate) diol terminated (PMPA), isophorone‐diisocyanate (IPDI) and 2‐hydroxyethyl methacrylate (HEMA). Poly(3‐hydroxyl‐butyrate‐co‐3‐hydroxylvalerate) (PHBV) is chosen to improve the processability of the UPM. UPM/PHBV blend ultrafine fibers are successfully electrospun with a proper mass ratio of UPM to PHBV in dichloromethane solution. The fibers are thermally crosslinked after electrospinning. Measurement results indicate that the average diameter of the fibers is about 1 μm and the crosslinked fibers have good solvent‐stability and thermal‐stability. This novel fiber has potential applications in filtration and protective coating. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 107:2142–2149, 2008     

Synthesis and swelling properties of new crosslinked polyorthocarbonates

Crosslinked polyorthocarbonates were synthesized by the condensation of tetraethyl orthocarbonate and hydroxyl functional monomers. The main goal of this study was to produce a solvent‐absorbent polymer with a high absorption capacity and to use these polymers for the removal of organic solvents from the environment and the recovery of these solvents. The synthesized polymers were characterized by Fourier transform infrared spectroscopy, solid‐state ¹³C‐NMR spectroscopy, thermogravimetric analysis, and differential scanning calorimetry. All of the polymers (except Poly 1 and Poly 2 ) had a high and fast uptake ability for organic solvents, such as tetrahydrofuran, dichloromethane, benzene, and acetone. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Synthesis and thermal properties of polyurethane–polysiloxane crosslinked polymer networks

Polysiloxane–polyurethane crosslinked polymer networks (PSI–PU) were synthesized in solution by polymerization of oligosiloxanes containing γ‐hydroxy propyl groups with polymethane polyphenyl polyisocyanate. Polyether‐based polyurethane and polyester‐based polyurethane were also prepared by a “one‐shot” method. Their thermal properties were studied by thermogravimetric analysis. It was observed that the thermal stability of PSI–PU was better than that of polyether‐based polyurethane and polyester‐based polyurethane, and an inert atmosphere had no effect on decomposition of polyurethanes below 350°C. It was found that polyurethane–polysiloxane crosslinked polymer networks decomposed slower in oxygen than in nitrogen in the temperature range of 350–550°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 310–315, 2003     

二茂铁甲酸封端不饱和聚酯的固化及热性能研究

以乙二醇、反丁烯二酸为原料合成的不饱和聚酯作为主链,二茂铁甲酸(FCA)作为封端剂,合成了含二茂铁基的不饱和聚酯(RFc),采用红外光谱对产物结构进行了表征。采用DSC及TGA研究了不同二茂铁甲酸含量对不饱和聚酯树脂固化性能和热稳定性的影响。结果表明,随着二茂铁甲酸含量的增加,RFc树脂固化反应活性减弱,热稳定性下降。其最高放热峰温度在171～173℃,且具有比较宽的加工温度范围(152～195℃),符合模塑料固化工艺要求。树脂的耐热性较好,初始热分解温度约为340℃,N2气氛下600℃残炭率可达19.76%。     

Synthesis and properties of crosslinked poly(arylene ether nitriles) containing pendant phthalonitrile

In this study, poly(arylene ether nitriles) containing pendant carboxyl groups (PEN‐COOH) was first synthesized via nucleophilic aromatic substitution reaction from phenolphthalein, hydroquinone and 2,6‐dicholorobenzonitrile. Then, poly(arylene ether nitriles) with pendant phthalonitrile groups (PEN‐CN) was obtained via the Yamazaki–Higashi phosphorylation route from 4‐(4‐aminophenoxy)phthalonitrile (APN) with PEN‐COOH in the presence of CaCl₂, thus the phthalonitrile as pendant groups in PEN‐CN were easily crosslinked by further thermal treatment. The effect of crosslinking density on the thermal stabilities, dielectric properties and water absorption of the PEN‐CNs was investigated. These results showed that the T_g of PEN‐CN was improved from 182 to 213°C, dielectric constant (ε) was increased from 3.1 to 3.9, and dielectric loss (tan δ) was decreased from 0.090 to 0.013 at 1 kHz. The water absorption of PEN‐CNs after thermal crosslinking was <1.01 wt %, which showed excellent water resisting property. Therefore, this kind of poly(arylene ether nitriles) containing pendant phthalonitrile could be a good candidate as matrix resins for high‐performance polymeric materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

碱水易溶聚酯热降解动力学研究

利用热重分析法(TGA)对自制的碱水易溶聚酯(ASHPET)的热降解动力学进行了研究,并与常规PET和国外某公司碱水易溶聚酯(K-COP)进行了比较。结果表明:几种ASHPET的热稳定性略低于常规PET;三种自制的ASHPET的热稳定性不低于国外某公司的K-COP。     

Effect of adding feldspar on free volume properties of crosslinked polyester studied by positron annihilation lifetime spectroscopy

Positron annihilation lifetime spectroscopy (PAL) was applied to study the feldspar effect on the free volume properties of crosslinked polyester based on neopentyl glycol, succinic acid, phthalic anhydride, and maleic anhydride. The measurements have been carried on the polyester resin samples cured with three crosslinking agents namely styrene (SS) or styrene/methyl methacrylate (SM) or styrene/acrylonitrile (SA) comonomers mixtures in the ratios of 2 : 1 and loaded with different concentrations of feldspar in the range from 0 to 80 wt %. The free volume parameters (size and fractions of holes) depend on type of the crosslinking agent as well as the feldspar content added to the polyester. The results are supported by a significant variation in the nanoscale free volume hole size distributions. Moreover, the correlation between positron annihilation parameters and electrical parameters was discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and characterization of fluorine-containing polyester based on phthalic anhydride and tetrafluoropropyl glycidyl ether

Fluorine-containing polyester (FPE) was synthesized by the reaction of phthalic anhydride, epichlorohydrin, and 2,2,3,3-tetrafluoropropyl glycidyl ether (TFGE) at the catalysis of tetraethylammonium bromide using 1,4-butanediol as the initiator. The structure of FPE was characterized by ¹H NMR and ¹⁹F NMR, and the result showed that the fluorine in TFGE was introduced into FPE. Fluorine content in FPE was determined by oxygen-flask combustion and fluoride selective electrode. It was found that fluorine content in FPEs increased with the increase of TFGE content. The wettability of water and oil on the cured coating based on FPE was investigated by contact angle meter. Contact angles of water and diiodomethane on the cured coatings first increased with the increase of the fluorine content in FPEs and then remained constant. The X-ray photoelectron spectroscopic analysis showed that the F/C molar ratio on the coatings surface was much higher than the overall F/C molar ratio, which indicated that fluoroalkyl groups in FPEs had enriched on the coatings surface. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and characterization of crosslinked polyurethane dispersions based on hydroxylated polyesters

Stringent environmental regulation has endowed dispersible coatings with excellent property profiles in industrial applications. In this aspect, aqueous polyurethane dispersions (PUDs) are of special interest. The present study reports on the synthesis of hydroxylated polyester (HP) based polyurethane polyols containing internal carboxyl group with different diisocyanates. These polyurethane polyols were partly acetoacetylated with ethyl acetoacetate to incorporate β‐ketoester in the polyurethane polyol backbone. The synthesized polyols were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and differential scanning calorimetry. Polyurethane polyols and their acetoacetylated cousins were used to develop PUDs. Particle size of the reactive PUDs was evaluated by a particle size analyzer. PUDs were crosslinked with hexamethoxy methyl melamine and their film properties were studied by dynamic mechanical and thermal analyzers and thermogravimetric analyses. The effects of different diisocyanate and acetoacetylation on the stability of reactive dispersion and properties of the crosslinked films were evaluated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 368–380, 2006     

新型含硼苯并噁嗪的合成及其与环氧树脂共混热性能

以乙醇胺、硼酸为原料合成硼酸乙醇胺酯（BAE）,再用所得硼酸乙醇胺酯与多聚甲醛、苯酚反应,合成含硼苯并噁嗪（BAE-BOZ）。将所得BAE-BOZ高温固化,BAE-BOZ和环氧树脂E-51按照不同的质量比进行熔融共混,并经高温固化。采用FT-IR,¹H NMR 和¹³C NMR等分析了BAE-BOZ的化学结构,证明了产物为目标产物;采用DSC对BAE-BOZ的固化特性进行研究;采用TG 分析了含硼乙醇胺型苯并噁嗪poly（BAE-BOZ）和BAE-BOZ/E-51共聚物的热稳定性。结果表明：BAE-BOZ在218℃出现了固化峰;BAE-BOZ的硼含量达到8.67%,在N₂条件下,poly（BAE-BOZ）的热分解温度为302℃,在426℃时热分解速率最快,800℃的残炭率为58.08%,与未经硼改性的乙醇胺型苯并噁嗪（E-BOZ）相比,热分解温度提高40℃,残炭率提高了16.28%;BAE-BOZ/E-51共聚物的热分解温度达到343℃,热性能得到进一步提高。