Selective Localization of MWCNT in Poly (Trimethylene Terephthalate)/Poly Ethylene Blends: Theoretical Analysis, Morphology, and Mechanical Properties

Abstract

Theoretical analysis is carried out to predict the nature of selective localization of multi‐walled carbon nanotubes (MWCNTs) in poly(trimethylene terephthalate/polyethylene (PTT/PE) blends. In agreement with theoretical data experimental results clearly indicate that MWCNT prefers to get associated with PTT phase than with PE. Molecular interactions responsible for such selective localization of MWCNT to PTT component can be attributed to mutual and collective π–π interactions possible between the aromatic moieties present in PTT and MWCNT. In addition, the reinforcing effect of MWCNT in the PTT/PE system was determined using tensile analysis and the morphological features of blends and blend nanocomposites are studied using scanning electron microscope (SEM). Compared to the PTT/PE blend system MWCNT incorporated blend nanocomposites show better mechanical properties. The elongation at break of the blend system is seen to rise with increasing amount of PE content. Among various blend nanocomposites, we have investigated the nanocomposites with higher PTT content show higher tensile strength and Young's modulus. The blend nanocomposite with 90/10/1 composition shows 12% increment in Young's modulus and as much as 80% increment in tensile strength compared to 90/10 blend system which signifies the role MWCNT plays in the blend system.

Effect of blend composition and related morphology on the quasi-static fracture performance of LLDPE/PP blends

“…This is due the absence of strong interactions between the two polymer components [29,32]. More details are given in a previous work [21], and are similar to other authors findings [5,9,33,34]. Regarding the morphology near the weld line, elongated particles are present probably due to the elongation stresses induced by flow during mold filling.…”

“…The necking during stretching of a polymer is, in fact, an expression of the yield behavior of the material mainly attributable to the morphological structure and the nature of the interface between the two phases [22]. It was observed a negative deviation from a rule of mixtures typically due to the embrittlement common in incompatible plastic blends [34].…”

Influence of Different Copolymer Based Compatibilizers on Performance of Pristine and Recycled PP/PE blends

“…While the blend without compatibilizer (PR-0) presents mainly spherical domains, the blend PR-10MB1 exhibits inclusions with an elliptically shaped structure, and the PR-10MB2, PR-10MB3 and PR-10MB4 blends show a co-continuous phase structure. As reported by several authors [23][24][25][26], polyolefin blends are immiscible and incompatible. For incompatible systems like PR-0, interfacial tension is high, i.e., spherical droplets are mainly generated during cooling, minimizing surface energy.…”

“…a salami type structure in which a polypropylene matrix with islands of polyethylene that contain occlusions of the matrix material is observed. Again, MB4 addition changes the morphology of the second phase from spherical shaped to elliptical or nondefined shaped domains [23,25,26,29]. The last analysis indicates that recycled blends seem to be similar to pristine blends in terms of the above characteristics.…”

“…smaller particles, ellipses and co-continuous structures. Another distinctive characteristic is the adhesion between phases [23,27,28]. In the case of PR-0 and PR-10MB1, dark zones (voids) indicative of unbounded phases are clearly seen, while no evidences of detachment between phases are observed in PR-10MB2, PR-10MB3 and PR-10MB4.…”