Blends of ethylene 1-octene copolymer synthesized by Ziegler-Natta and metallocene catalysts. I. Thermal and mechanical properties

Abstract

ABSTRACT:The thermal, viscoelastic, and mechanical behaviors of three binary blends of ethylene 1-octene copolymer (EOC) regarding the melt index and density, one component made by Ziegler-Natta (FA and RF in abbreviation of the commercial name) and the other by metallocene catalysts (FM, EN and PL in abbreviation of the commercial name), have been investigated to understand molecular mechanism of the blends. Thermal studies reveal that the two constituents in the three blends exclude one another during crystallization, implying a phase separation. Viscoelastic properties show a single ␤ or ␥ transition in all the compositions, suggesting a miscibility in the amorphous region. The tensile modulus, yield stress, maximum strength at break, and elongation at break follow the rule of mixtures if the comonomer content does not differ too much. Otherwise, the modulus and yield stress are negatively deviated, whereas elongation at break is positively deviated from the weight-average value. The tensile properties of film at yield and break in the machine direction is increased with an addition of FM in the FA ϩ FM blend. Although all three blends form separate crystals in the crystalline state, a correlation exists between the mechanical properties and the density of EOCs.

Potential of sodium alginate/titanium oxide biomembrane nanocomposite in DMFC application

“…The hydrogen bonding formation is resulted in a robust interfacial linkage, which leads in superior mechanical properties. 61,62 Elongation at break is also known as flexibility. This component was positioned in free dimensions of SA biopolymer, which serve to obstacles the sliding of SA biopolymer molecule if any outer strength forced on membrane composite.…”

Structural and Mechanical Properties Changes of Ethylene‐α‐olefin Copolymer Blends Induced by Thermal Treatments and Composition

“…[35] This smooth change of b relaxation with addition of C 8 VLDPE confirms the miscibility in the amorphous phase. [6] It also can be seen that the two different thermal treatments result in small difference in the b relaxation temperature, suggesting that the rotational motion of the branches in polyethylene is insensitive to different thermal treatments.…”

“…Similar results have been found for the blends of LLDPE (Ziegler-Natta) and LLDPE (metallocene). [6] Conclusion The study of structure and properties of single-site catalyzed polymer blends is a timely important issue because of their significant industrial applications. The investigation of single-site catalyzed blends of ethylene-a-butene with short-chain branches and ethylene-a-octene with both long and short chain branches showed the strong dependency of the thermal history and composition.…”

“…polyethylenes and poly(propylene)s. [4][5][6][7][8][9] In particular, the use of elastomeric ethylene-a-olefins as impact modifiers has attracted great attention. [10] Blends of LLDPE and low-density polyethylene (LDPE) are often used for film manufacture because of their good processability and excellent mechanical properties.…”

“…[13] The other factors that define crystalline state are the molar mass, molar mass distribution, chemical nature of the comonomer, the quantity and distribution of the branches, composition ratio and miscibility of the materials. [4][5][6][7][8][9] In the present work, we focus on the influence of thermal history and composition on the structure, morphology and mechanical properties of the blends. Two different thermal treatments were applied: slow cooling in an oven and quenching from the melt.…”