聚(对苯二甲酸乙二醇酯-co-对苯二甲酸异山梨醇酯)预结晶及固相聚合研究

研究了不同异山梨醇(ISB)含量的聚(对苯二甲酸乙二醇酯-co-对苯二甲酸异山梨醇酯)(PEIT)共聚酯预结晶及固相聚合工艺。探讨了温度、时间与PEIT共聚酯预结晶温度、固相聚合反应速率之间的关系;利用差式扫描量热仪(DSC)分析研究PEIT共聚固相聚合前后的热性能变化情况。结果表明:随着ISB用量的增加,PEIT共聚酯结晶困难,预结晶时间增加,固相聚合反应速率减慢;随着温度升高,PEIT共聚酯固相聚合反应速率加快,但仍慢于聚对苯二甲酸乙二醇酯(PET);固相增粘后PEIT共聚酯玻璃化转变温度(Tg)与ISB含量呈线性上升关系。     

含间苯二甲酸、2,6-萘二甲酸、2-氯代对苯二酚双醋酸酯等单体的全芳香族共聚酯——第Ⅱ报:共聚芳酯流变性能的研究

本文研究了含有间苯二甲酸(IPA)、2,6-萘二甲酸(2,6-NDA)、2-氯代对苯二酚双醋酸酯(CIHQA)、对羟基苯甲酸醋酸酯 (PABA)和含有对苯二甲酸(TPA)、2,6-NDA、CIHQA、IPA的两类全芬香族共聚酯的流变性。研究结果表明,芳香族共聚酯的粘度受到剪切速率的强烈影响,出现了所谓“切力变稀”现象。这种现象随熔体的温度升高或分子链中不对称基团含量的增加而减弱。芳香族共聚酯的熔体有较高的粘流话化能和较低的弹性。     

水溶性共聚酯的合成研究

以聚对苯二甲酸乙二醇酯(PET)为基体,引入第三单体间苯二甲酸乙二醇酯-5-磺酸钠(SIPE)和第四单体间苯二甲酸(IPA),通过直接酯化-缩聚工艺路线合成水溶性共聚酯,系统研究了二元酸配比、SIPE添加量对共聚酯的合成和常规性能的影响,利用核磁共振定性分析了共聚酯的大分子链序列结构。结果表明SIPE主要影响共聚酯的流动性能和常规性能,IPA主要影响共聚酯的耐热性能。核磁表明SIPE和IPA均成功引入共聚酯大分子链结构中,且符合多单体改性和高比例IPA改性的分子序列结构特点。     

间苯二甲酸与二甘醇对PET共聚改性的研究

用间苯二甲酸 (PIA)、二甘醇 (DEG)作改性剂合成共聚酯 ,利用DSC分析加入 2 %～ 8% (mol)PIA对改性共聚酯的影响。结果表明 ,PIA作为第三组分、DEG作为第四组分参与共聚反应 ,合成的共聚酯的特性粘数下降 ,结晶速率减慢 ,结晶度降低 ,玻璃化温度和熔点均有所下降。DEG的添加量以 0 .5 % (质量分数 )为宜。     

催化剂用量对共聚酯合成及性能的影响

合成了不同催化剂用量的PTA IPA EG三元共聚酯 ,通过TGA及常规性能测试 ,对合成工艺、共聚酯性能及固相增粘等进行了研究。结果表明 :在一定范围内 ,增加催化剂用量 ,缩聚反应速度加快 ,聚合时间缩短 ,固相增粘速度稍有增加 ;但同时共聚酯L值下降 ,外观发灰 ,共聚酯耐热性下降     

高收缩聚酯合成及其纤维的收缩性能

在聚酯中添加间苯二甲酸(IPA)和具有侧链结构的新戊二醇(DTG),制成了高收缩聚酯切片及纤 维。研究了IPA,DTG的添加量对切片的热性能和纤维的热收缩率及经时稳定性的影响。研究表明,随着 IPA、DTG加入量增加,共聚酯的结晶性能降低,而纤维的收缩率则呈规律提高,可达到50.0％以上,并具有 较好的经时稳定性。     

低熔点共聚酯的流变性研究

由对苯二甲酸(PTA)、间苯二甲酸(IPA)、丁二醇(BDO)共缩聚制备了低熔点共聚酯。采用Rosand RH7型毛细管流变仪对不同摩尔百分比组成的共聚酯的流变性进行了研究。结果显示:低熔点共聚酯是典型的假塑性流体,随着温度升高,剪切黏度下降,非牛顿指数增大;随着剪切速率的增大,低熔点共聚酯黏流活化能降低。比较了两种组成的低熔点共聚酯的流变性,发现随着第三单体IPA的增加,低熔点共聚酯的剪切黏度降低,非牛顿指数减小。分析了第三单体对低熔点共聚酯流变行为的影响。     

高性能聚芳酯纤维的研制和表征

介绍了热致性液晶聚芳酯纤维的制备。选用双酚A、对苯二甲酸、间苯二甲酸为单体进行熔融聚合,制得具有不同相对分子质量的双酚A-对/间苯二甲酸共聚酯,探索了后续固相聚合工艺,研究了后续固相聚合对原熔融聚合物相对分子质量、热性能以及力学性能的影响。原聚合物再经固相聚合及不经固相聚合的两种聚芳酯在不同的纺丝和热处理工艺条件下,可以获得力学性能相近的聚芳酯纤维,为进一步研制热致液晶型聚芳酯纤维生产路线提供可靠的工艺数据。     

间苯二甲酸生产技术及应用

介绍了间苯二甲酸(IPA)的生产技术,重点介绍了空气液相氧化法生产IPA,其工艺分3个阶段, 即粗IPA的制备,精IPA制备、母液及残渣的处理。IPA主要应用在酸改性共聚酯、不饱和聚酯及表面涂料方面。预计在今后几年中,IPA在共聚酯方面的应用将得到迅速发展。     

聚酯瓶片PET性能与间苯二甲酸含量影响因素的研究

研究了不同间苯二甲酸(IPA)含量对基础切片(CP)、增粘切片、吹瓶等过程的影响,IPA含量越多,越有利于得到透明性较好的瓶子,但同时随着IPA含量增多,瓶子稳定性能也有下降的趋势,必须正确选择好IPA含量。     

PEIT共聚酯及其复合纤维的性能研究

研究了系列不同间苯含量(0相似文献   

高分子量PET／60PHB热致性液晶共聚酯的结构与性能

研究了固相缩聚过程中PET/60PHB共聚酯结构性能的变化。随着反应的进行,分子量增大,分子量分布宽度指数变小;玻璃化温度略增,熔融温度增加幅度较大;热稳定性明显提高。预聚体中主要存在PET的低共熔物或部分同二质晶,固相缩聚反应使PET结晶消失,PHB结晶形成并完善。固相缩聚大大改善了共聚酯的可纺性,用[η]为0.95dL/g的共聚酯制得断裂强度达到高强范围(1GPa)的初生纤维。     

Thermal decomposition behavior of carbon nanotube reinforced thermotropic liquid crystalline polymers

Thermotropic liquid crystalline polymers (TLCP), 4‐hydroxybenzoic acid (HBA)/6‐hydroxyl‐2‐naphthoic acid (HNA) copolyester, and HNA/hydroxylbenzoic acid (HAA)/terephthalic acid (TA) copolyester reinforced by carbon nanotube (CNT) were prepared by melt compounding using Hakke internal mixer. The thermal behavior and degradation of CNT reinforced HBA/HNA copolyester and HNA/HAA/TA copolyester have been investigated by dynamic thermogravimetric analysis under nitrogen atmosphere in the temperature range 30 to 800°C to study the effect of CNT on the thermal decomposition behavior of the TLCP/CNT nanocomposites. The thermal decomposition temperature at the maximum rate, residual yield, integral procedural decomposition temperature, and activation energy for thermal decomposition was studied to investigate thermal stability of TLCP/CNT nanocomposites. The thermal stability of CNT reinforced HBA/HNA copolyester was increased by addition of a very small quantity of CNT and the residual weight was 42.4% and increased until 50.8% as increasing CNT contents. However, the thermal stability of CNT reinforced HNA/HAA/TA copolyester was decreased initially when a very small quantity of CNT added. The residual weight was decreased from 50.4% to 45.1%. After addition of CNTs in the TLCP matrix, the thermal stability of CNT reinforced HNA/HAA/TA copolyester increased as increasing content of CNT and the residual weight was increased until 53% as increasing CNT contents. The activation energy was calculated by multiple heating rate equations such as Friedman, Flynn‐Wall‐Ozawa, Kissinger, and Kim‐Park methods to confirm the effect of CNT in two different TLCP matrices. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

高收缩共聚酯合成性能与成纤性能研究

通过共聚酯PEIT(间苯二甲酸、对苯二甲酸、乙二醇共聚物)的合成及其全拉伸丝(FDY)纺丝的成功实验,研究了高收缩PEIT共聚物合成工艺中共聚组分间苯二甲酸(IPA)的摩尔百分数对共聚酯PEIT的玻璃化温度、熔点的影响,探讨了该PEIT共聚物的结晶性能及其纺丝工艺条件对高收缩纤维性能的影响。     

The thermal shrinkage of the drawing poly(ethylene isophthalate terephthalate) copolyester films

The objective of this study is to use the copolymerization method to improve the thermal shrinkage property of poly(ethylene terephthalate) (PET), so that the resultant copolyester can be used for the application of thermal shrinkage packing materials. The poly(ethylene isophthalate terephthalate) (PEIT) copolyester films were prepared and studied. The thermal shrinkage rate of PET films and the thermal shrinkage rate of the copolyester films were measured by using a thermomechanical analyzer (TMA). The thermal shrinkage of copolyester was found to be dependent on such factors as composition, molecular weight, and draw temperature. The highest thermal shrinkage was obtained when the copolymer contained 40 mol % of ethylene isophthalate. Its shrinkage ratio and shrinkage rate were consistently 1.3 and 2.4 times those of PET. The increase of molecular weight and decrease of drawing temperature resulted in the increase of the thermal shrinkage. The best drawing temperature range was between glass transition temperature and soft temperature of the copolymer. The relationship of shrinkage rate and temperature indicate that the shrinkage mechanism of the copolyester belongs to two-step thermal shrinkage.     

含两种不同共聚组分改性聚酯的结晶速率

添加己二酸、间苯二甲酸,聚乙二醇对PET进行改性,合成样品。用DSC法研究合成共聚物的等温结晶动力学。结果表明,在所选择的温度范围内,共聚物很好的符合Avrami方程。随温度的升高,共聚物的结晶速度常数K和Avrami指数n逐渐减小,结晶速度G逐渐降低。含2种柔性组分的共聚酯随着一种柔性组分含量的增加,结晶速率G上升;含一种刚性一种柔性组分的共聚酯随刚性组分含量的增加,结晶速率G下降。     

2,5-Furandicarboxylic acid as a sustainable alternative to isophthalic acid for synthesis of amorphous poly(ethylene terephthalate) copolyester with enhanced performance

2,5-furandicarboxylic acid (FDCA), a bio-based monomer, was taken as a sustainable alternative to isophthalic acid (IPA) for the modification of poly(ethylene terephthalate) (PET). Results showed that FDCA was more effective than IPA in terms of reducing the crystallization activity of PET, because FDCA is more rigid and highly polar, which will hinder the PET chain packing during crystallization process. Moreover, modification of PET with FDCA resulted in copolyester with higher glass transition temperature, higher tensile modulus, better optical clarity, and gas barrier property, compared to those of IPA. With the addition of 20 mol % FDCA, the resulted copolyester poly(ethylene 2,5-furandicarboxylate-co-ethylene terephthalate) (PEFT 20) was able to keep high transparency even after being annealed at 110 °C for 40 min. However, when 20 mol % of IPA was added, poly(ethylene isophthalate-co-ethylene terephthalate) (PEIT20) easily turned opaque under the same heat treatment. Therefore, less amount of FDCA was required in order to obtain the PET copolyester with better performance. The result indicated that FDCA had great potential to substitute IPA for the modification of PET from the point of view of industrial application. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47186.     

间苯二甲酸改性聚醚酯弹性体的合成与表征

用间苯二甲酸(IPA)作为改性剂,对以对苯二甲酸二甲酯(DMT),1,4–丁二醇(BDO),聚四氢呋喃醚(PTMG)和抗氧剂1010为原料以及钛酸丁酯为催化剂合成的软硬段为7∶3的聚醚酯弹性体进行改性,以提高其纤维的低温回弹性能。通过改变IPA与DMT的物质的量比(1∶5~1∶15),成功地合成了一系列的IPA改性聚醚酯弹性体(PBITG–1~PBITG–5),并对其结构、热性能、力学性能和纤维回弹性能进行了测试和表征。通过对IPA改性聚醚酯弹性体的傅立叶变换红外光谱和核磁谱图分析可知,成功地合成了IPA改性聚醚酯弹性体。从差示扫描量热测试结果分析得知,随着IPA含量的降低,所合成的IPA改性聚醚酯弹性体的熔点逐渐增加。热重分析结果表明,不同IPA含量的聚醚酯弹性体都具有良好的热稳定性能,起始分解温度都高于365℃。通过单纤强力仪测试表明,同一拉伸倍数下,随着IPA含量的减少,聚醚酯弹性体纤维的断裂强度和断裂伸长率都有所增加。低温回弹性能测试结果表明,IPA的加入的确能提高聚醚酯弹性体纤维的低温回弹性能,其中,PBITG–1纤维拉伸1倍时对应的低温回弹率最大,为97.92%。     

PET-PEN共聚酯对PET/PEN共混物的增容作用及其机理

使用聚对苯二甲酸乙二酯(PET)-聚萘二甲酸乙二酯(PEN)无规共聚酯作增容剂,通过双螺杆挤出机熔融共混,制备了不同PET-PEN共聚酯用量的PET/PEN共混物,采用差示扫描量热分析、热重分析、热变形温度测试以及力学实验等方法,研究了该共混物的相容性及其它性能。结果表明,PET-PEN共聚酯对PET/PEN共混物具有明显的增容作用,能有效提高PET/PEN共混物的热稳定性,其用量越高,热稳定性提高越明显,当PET-PEN共聚酯用量为15质量份时,起始失重温度提高了20.3℃。PET-PEN共聚酯增容剂能提高PET/PEN共混物的维卡软化温度、拉伸和弯曲性能以及冲击性能,当PET-PEN共聚酯用量为5质量份时,增容改性的综合效果最好。