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

Abstract

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

Dielectric characterization of thermally aged recycled Polyethylene Terephthalate and Polyethylene Naphthalate reinforced with inorganic fillers

“…PEN and PET can also be mixed together, and their blends used in different applications, especially in electric and electronic devices, thanks to their unique thermal and dielectric properties, which can remain stable over a wide temperature domain . Several works have reported on comparison studies between PET and PEN.…”

A comprehensive study on morphological and rheological behavior of poly(ethylene terephthalate) and poly(ethylene‐2,6‐naphthalene) nanocomposite blends in presence of graphene

“…Commercial aromatic polyesters of poly(ethylene terephthalate) (PET) and poly(ethylene‐2,6‐naphthalene) (PEN), with their unique properties, are important available engineering thermoplastics used in various applications, such as films, fibers, bottles, and hot filling containers, and in high‐performance applications, such as supports in flexible electronic devices . They have low permeability toward gases, good impact strength, good creep resistance, and resistance to chemical attack.…”

“…Nowadays, there is great interest in flexible electronic devices . It is claimed in much research that PET and PEN are the best choices for use in these applications because of their unique mechanical properties and good manufacturability.…”

“…The development of PET/PEN blends can lead to a new generation of materials with a unique set of properties with a competitive cost. The PET/PEN blends offer advantages over PET in their mechanical, thermal, viscoelastic, and barrier properties .…”

“…Although single blending may be a promising solution, faulty mechanical properties and thermal stability of PET and PEN have generally hindered their practical applications in a broad range of industrial uses. To overcome such limitations, it would be interesting to use fillers, either a polyester or its blends, to optimize their cost and properties .…”