啤酒瓶用共缩聚PET/PEN的研究

采用对苯二甲酸二甲酯(DMT)与2，6-萘二甲酸二甲酯(DMN)合成了聚对苯二甲酸二乙酯(PET)和聚2，6-萘二甲酸二乙酯(PEN)共缩聚物，研究了PEN用量对共缩聚PET／PEN热性能的影响，并研究了采用PET／PEN制成的啤酒瓶的物理性能、气体阻隔性能和贮藏性。结果表明：PET／PEN的性能与普通聚酯切片的相近，PEN质量分数为30％的PET／PEN制成的啤酒瓶可耐95℃高温，对O2、CO2气体的阻隔性比普通PET瓶提高6倍。     

纳米复合塑料PET/PEN/NCL在啤酒瓶上的应用

用对苯二甲酸二甲酯（DMT）与2，6-萘二甲酸二甲酯（DMN）两种单体，共缩聚为聚对苯二甲酸二乙醇酯（PET）和聚2，6-萘二甲酸二乙酯（PEN）共聚物。讨论了不同用量的纳米累托土（NCL）和PEN对共聚物PET／PEN／NCL及切片性能的影响。结果表明：纳米PET／PEN／NCL复合材料的合成工艺与普通聚酯切片的合成工艺相近，ω（PEN）=6％、ω（NCL）=3．0％的纳米啤酒瓶可耐105℃高温，对O2、CO2气体的阻隔性比PET瓶提高5—6倍，保质期可达5个月，运输和贮存比较安全，可满足工业需求。     

PET/PEN/NCL纳米啤酒瓶的研制

用对苯二甲酸二甲酯、2,6-萘二甲酸二甲酯两种单体与乙二醇进行酯交换反应制备了(对苯二甲酸乙二N／2,6-萘二甲酸乙二酯)共聚物(PET／PEN),讨论了纳米累托石(NCL)和PEN不同含量对PET／PEN／NCL纳米复合材料性能的影响。结果表明,PET／PEN／NCL纳米复合材料的合成工艺与普通PET的合成工艺相近;当PEN质量分数为6％、NCL质量分数为3％时制得的PET／PEN／NCL纳米啤酒瓶可耐105℃高温,对O2、CO2的阻隔性比PET瓶提高5—6倍。     

PET/PET-co-PEN共混物的中空吹塑研究

介绍聚对苯二甲酸乙二酯(PET)／PET共聚聚萘二甲酸乙二酯(PET—co—PEN)共混物的成型加工特性，探讨利用加工PET的设备、两步法注射拉伸吹塑工艺，生产耐热和阻隔PET／PET-co-PEN共混物制品的可行性。结果表明，为了得到理想的制品外观和性能，需要对挤出螺杆、加工工艺参数、型坯设计和拉伸比进行改进。     

高阻隔耐热PET/PEN饮料瓶的研制

用双螺杆挤出机研究了熔融挤出工艺、原料的选择及配比对聚对苯二甲酸乙二酯(PET)/聚对萘二甲酸乙二酯(PEN)共混物耐热性和阻隔性的影响,并利用差示扫描量热仪、核磁共振仪进行了性能表征。结果表明,PET与PET-PEN共聚酯容易熔融共混,即在无定形态相容;随挤出时间和温度的增加,PET/PEN共混物的冷结晶温度升高、熔点降低、阻隔性降低而玻璃化转变温度不变;随PET-PEN含量的增加,共混物的阻隔性和耐热性得到改善。用注-拉-吹工艺成型可得到PET/PEN共混物饮料瓶,其耐热性和对氧气的阻隔性比纯PET瓶高,且随PET-PEN含量的增加而提高。     

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。     

聚萘二甲酸乙二醇酯研究开发进展

讨论了直接酯化法和酯交换法生产PEN的酯化反应条件和缩聚反应条件,分析了PEN均聚物和共聚物及PET的生产成本,介绍了PEN的优异性能(例如耐热性、阻隔性、机械性能、耐化学药品性、抗紫外线性等)及其在薄膜、包装容器、工业纤维和注塑部件中的应用,并指出了我国开发PEN的有利条件。     

2,6-萘二甲酸提纯方法

2,6-萘二甲酸(简称2,6-NDCA)结构上具有高度的对称性,是合成多种高性能含萘聚合物的重要单体。由2,6-NDCA与乙二醇反应得到聚2,6-萘二甲酸二乙酯(简称PEN),其多方面性能均优于对苯二甲酸二乙酯(PET)。2,6-萘二甲酸粗产物中有许多杂质存在,不同的制备方法杂质种类和含量也不完全相同,这将直接影响聚合反应和PEN的质量。因此,2,6-萘二甲酸必须进行纯化,使之达到聚合级的质量要求。综述几种提纯2,6-萘二甲酸的方法。     

车灯装饰圈用PBT/PET合金的成型加工

研究了聚对苯二甲酸丁二醉酯/聚对苯二甲酸乙二醇酯(PBT/PET)合金的流变特征;并结合PBT/PET合金的特点,研究了干燥工艺、模其设计、注塑设备选择、注塑加工工艺对制品性能的影响,对优化PBT/PET合金材料的注塑工艺条件具有指导意义.     

PET/MMT纳米复合材料的研究进展

综述了聚对苯二甲酸乙二酯(PET）/蒙脱土(MMT)纳米复合材料的2种制备方法、性能及其表征方法。MMT对PET的改性可以提高PET的阻隔性和结晶速率．并使PET拉伸模量和热变形温度大幅度提高,是目前PET改性的新方向。     

Oxygen and carbon dioxide transport through high barrier polyester blends

The transport of oxygen and carbon dioxide through a set of random copolymer films based on poly(ethylene terephthalate) (PET) and poly(ethylene 2,6‐naphthalate) (PEN) were explored. Diffusivity and permeability of both gases decreased with increasing PEN content. The oxygen and carbon dioxide diffusion coefficients decreased 74 and 82% from pure PET to pure PEN, respectively. The presence of stiffer PEN moieties had an effect on the glass transition temperature (T_g) of PET/PEN blends and gas barrier. In the complete range of tested blends, the differential scanner calorimeter analysis displayed a single value of thermal glass transition temperature. As the PEN content was increased, the fractional free volume (FFV) and the diffusion coefficients of the blends were decreased. The Doolittle equation provided the best fit for diffusivity and FFV and showed that the gas transport behavior was better understood when it was taken into consideration the cohesive energy of blends. As the PEN content in films was increased, their rigidity and the glass/rubber transition temperature were increased, and their capacity to be penetrated by small molecules like O₂ and CO₂ was decreased. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

阻隔性PET/PEN共聚酯的性能研究

对共聚型阻隔聚酯PETNx(x为共聚酯中NDA占羧酸总质量的百分比)的热性能、流变性能和阻隔性能进行了研究。结果表明,PETNx体系属于假塑性流体。PETNx的CO2气体阻隔性优于常规PET;随着PETNx中NDA含量的增加,共聚物的玻璃化温度呈线性增高。     

Morphology and barrier mechanism of biaxially oriented poly(ethylene terephthalate)/poly(ethylene 2,6‐naphthalate) blends

To improve the barrier properties of poly(ethylene terephthalate) (PET), PET/poly(ethylene 2,6‐naphthalate) (PEN) blends with different concentrations of PEN were prepared and were then processed into biaxially oriented PET/PEN films. The air permeability of bioriented films of pure PET, pure PEN, and PET/PEN blends were tested by the differential pressure method. The morphology of the blends was studied by scanning electron microscopy (SEM) observation of the impact fracture surfaces of extruded PET/PEN samples, and the morphology of the films was also investigated by SEM. The results of the study indicated that PEN could effectively improve the barrier properties of PET, and the barrier properties of the PET/PEN blends improved with increasing PEN concentration. When the PEN concentration was equal to or less than 30%, as in this study, the PET/PEN blends were phase‐separated; that is, PET formed the continuous phase, whereas PEN formed a dispersed phase of particles, and the interface was firmly integrated because of transesterification. After the PET/PEN blends were bioriented, the PET matrix contained a PEN microstructure consisting of parallel and extended, separate layers. This multilayer microstructure was characterized by microcontinuity, which resulted in improved barrier properties because air permeation was delayed as the air had to detour around the PEN layer structure. At a constant PEN concentration, the more extended the PEN layers were, the better the barrier properties were of the PET/PEN blends. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1309–1316, 2006     

PET/PEN共混体系的相容性和热性能研究

主要研究了 PET/PEN共混体系的相容性和热性能 ,发现 PET和 PEN具有较好的相容性 ,体系的耐热性和耐热水解性随 PEN量的增加而得到明显改善     

Thermal decomposition behavior of poly(ethylene 2,6‐naphthalate)/silica nanocomposites

Poly(ethylene 2,6‐naphthalate) (PEN) nanocomposites reinforced with silica nanoparticles were prepared by direct melt compounding. Dynamic thermogravimetric analysis was conducted on the PEN/silica nanocomposites to clarify the effect of silica nanoparticle on the thermal decomposition behavior of the resultant nanocomposites. There is a significant dependence of thermal decomposition behavior for PEN/silica nanocomposites on the content of silica nanoparticles and heating rate. The variation of the activation energy for thermal decomposition reflected the improvement of the thermal stability of the PEN/silica nanocomposites. The unique characteristics of silica nanoparticles resulted in physical barrier effect against the thermal decomposition, leading to the enhancement of the thermal stability of the PEN/silica nanocomposites. The incorporation of silica nanoparticles into the PEN matrix increased the storage modulus of the PEN/silica nanocomposites and made it possible for them to sustain higher modulus at higher temperature relative to pure PEN. POLYM. COMPOS., 2009. © 2009 Society of Plastics Engineers     

Interrelationship of thermal and mechanical properties of poly(ethylene terephthalate)/poly(ethylene 2,6‐naphthalate)/graphene nanocomposites

In the present work, attempts were made to investigate the thermal and mechanical properties of melt‐processed poly(ethylene terephthalate) (PET)/poly(ethylene 2,6‐naphthalate) (PEN) blends and its nanocomposites containing graphene by using differential scanning calorimetry and tensile test experimenting. The results showed that crystallinity, which depends on a blend ratio, completely disappeared in a composition of 50/50. By introducing graphene to PET, even in low concentrations, the crystallinity of samples increased, while the nanocomposite of PEN indicated reverse behavior, and the crystallinity was reduced by adding graphene. In the case of PET‐rich (75/25) nanocomposite blends, by increasing the nano content in the blend, the crystallinity of the samples was enhanced. This behavior was attributed to the nucleating effect of graphene particles in the samples. From the results of mechanical experiments, it was found in PET‐rich blends that by increasing the PEN/PET ratio, the modulus of samples decreased, whereas in the case of PEN‐rich blends, a slight increment of modulus is seen as a result of the increment of the PEN/PET ratio. The two contradicting behaviors were attributed to the reduction of crystallinity of PET‐rich blends by enhancement of PEN/PET ratio and the rigid structure of PEN chains in PEN‐rich blends. Unlike the different modulus change of PET‐rich and PEN‐rich blends, the nanocomposites of these blends similarly indicated an increment of modulus and characteristics of rigid materials by increasing the nano content. Furthermore, the same behavior was detected in nanocomposites of each polymer (PET and PEN nanocomposites). The alteration from ductile to rigid conduction was related to the impedance in the role of graphene plates against the flexibility of polymer chains and high values of graphene modulus. J. VINYL ADDIT. TECHNOL., 23:210–218, 2017. © 2015 Society of Plastics Engineers     

Thermal decomposition behavior of carbon‐nanotube‐reinforced poly(ethylene 2,6‐naphthalate) nanocomposites

Polymer nanocomposites based on poly (ethylene 2,6‐naphthalate) (PEN) and carbon nanotubes (CNTs) were prepared by direct melt blending with a twin‐screw extruder. Dynamic thermogravimetric analysis was conducted on the PEN/CNT nanocomposites to clarify the effect of CNTs on the thermal decomposition behavior of the polymer nanocomposites. The thermal decomposition kinetics of the PEN/CNT nanocomposites was strongly dependent on the CNT content, the heating rate, and the gas atmosphere. On the basis of the thermal decomposition kinetic analysis, the variation of the activation energy for thermal decomposition revealed that a very small quantity of CNTs substantially improved the thermal stability and thermal decomposition of the PEN/CNT nanocomposites. Morphological observations demonstrated the formation of interconnected or network‐like structures of CNTs in the PEN matrix. The unique character of the CNTs introduced into the PEN matrix, such as the physical barrier effect of CNTs during thermal decomposition and the formation of interconnected or network‐like structures of CNTs, resulted in the enhancement of the thermal stability of the PEN/CNT nanocomposites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009