Effect of blending small amount of high-density polyethylene on molecular entanglements during melt-drawing of ultrahigh-molecular-weight polyethylene

Takazawa, Ayaka; Kakiage, Masaki; Yamanobe, Takeshi; Uehara, Hiroki; Shimizu, Yui; Ohnishi, Takaya; Wakabayashi, Yasutake; Inatomi, Kei; Abe, Shigehiko; Aoyama, Kohki

doi:10.1016/j.polymer.2022.124528

Cited by 9 publications

(4 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, N e is assumed to be constant. Such a regime of deformation was observed for ultrahigh molecular weight polyethylene (UHMWPE) in experiments . In addition, we assume that the deformation is affine at the s ∝ N scale (Figure S6a–c).…”

Section: Resultsmentioning

confidence: 75%

Optimal Entanglement of Polymers Promotes the Formation of Highly Oriented Fibers

2022

View full text Add to dashboard Cite

Polymer fibers consist of macromolecules oriented along the fiber axis. Better alignment of chains leads to an increased strength of the fiber. It is believed that the key factor preventing formation of a perfectly oriented fiber is the entanglement of polymers. We performed large-scale computer simulations of uniaxial stretching of semicrystalline ultrahigh molecular weight polyethylene (UHMWPE). We discovered that there is an optimal number of entanglements per macromolecule necessary to maximize chain orientation in a fiber. Polymers that are entangled too strongly form less-oriented fibers. On the other hand, when polymers have too few entanglements per chain, they disentangle during stretching, and a strong fiber is not formed. We constructed a microscopic analytical theory describing both the fiber formation and disentanglement processes. Our work presents a novel view of the role of entanglements during fiber production and predicts the existence of an optimal number of entanglements per chain maximizing the fiber quality that scales with chain length as ∝ N 2/5. A total of 102 entanglements per chain is the optimum for UHMWPE having typical degree of polymerization of N ≈ 105.

show abstract

Section: Resultsmentioning

confidence: 75%

Optimal Entanglement of Polymers Promotes the Formation of Highly Oriented Fibers

2022

View full text Add to dashboard Cite

show abstract

“…They found that the entanglement of UHMWPE molecular chains significantly decreased. Takazawa et al 20 also found that adding a small amount of HDPE reduced the amount of tight molecular entanglements during melt‐drawing of UHMWPE chains.…”

Section: Introductionmentioning

confidence: 96%

Study on the synergistic effect of additives on the processing performance of UHMWPE/HDPE blends

Liu,

Jin,

Qin

et al. 2024

J of Applied Polymer Sci

View full text Add to dashboard Cite

The challenging melt processing of ultrahigh‐molecular‐weight polyethylene (UHMWPE) melt spinning hinders its efficiency and quality, which can be improved by processing aids that enhance its flowability. Building upon modifications of UHMWPE with high‐density polyethylene (HDPE), this article studies the effects of CaSt2, polyethylene glycol (PEG), silicone powder, and their compound additives on the processing performance of UHMWPE/HDPE blends. The modification effects and mechanisms are studied by analyzing processing torque, melt flow rate, viscoelastic activation energy, and rheological performance. The research results indicate that 1 wt% PEG significantly improves the processing flowability of UHMWPE/HDPE blends, and PEG mainly plays an internal lubrication role on the molecular chains of the blends. The combination of 0.5 wt% CaSt2 and 0.5 wt% silicone powder exhibits a synergistic effect of internal and external lubrication on the UHMWPE/HDPE blends melt processing, further improving the processing performance of UHMWPE/HDPE blends. Compared with unmodified blends, the maximum screw speed for obtaining qualified as‐spun filaments of UHMWPE/HDPE blends modified with CaSt2/silicone powder compound additives increases from 5 to 20 rpm, which means that the critical shear rate of the modified UHMWPE/HDPE blend melt processing is significantly improved. Meanwhile, the processing torque decreases by about 22%.

show abstract

“…While much literature has emphasized the significance of MW, the impact of the distribution between LMW and HMW chains in the blend has often been overlooked. 8,9 The split ratio (SR), representing the percentage of LMW chains in a BiPE resin, serves as a critical parameter, influencing reactor design parameters such as the volume of cascade reactors and the retention time of polymerization suspensions. This parameter plays a pivotal role not only in reactor design but also in shaping the mechanical, physical, and rheological properties of BiPE resins.…”

Section: Introductionmentioning

confidence: 99%

“…In the realm of BiPE resins, achieving tailored physical, mechanical, and rheological properties involves meticulous consideration of both the MW and the proportion of each constituent in the resin formulation. While much literature has emphasized the significance of MW, the impact of the distribution between LMW and HMW chains in the blend has often been overlooked 8,9 …”

Section: Introductionmentioning

confidence: 99%

Splitting for strength: Manipulating polymerization reactor split ratios to control mechanical and rheological properties in bimodal polyethylene resins

Jandaghian,

Sepahi,

Hosseini

et al. 2023

J of Applied Polymer Sci

View full text Add to dashboard Cite

This study integrates advanced mathematical modeling and experimental methodologies to investigate the simultaneous impact of modifications in the split ratio and molecular weight (MW) of chains on the rheological and mechanical properties of bimodal polyethylene (BiPE) resins. The outcomes underscored the viability of fine‐tuning the molecular weight distribution (MWD) of a BiPE resin by augmenting the MW of high molecular weight (HMW) chains while simultaneously diminishing their proportion in the final alloy formulation. In addition, the experimental results illuminated the prospect of attaining a targeted melt flow index for the final polymers by elevating the MW of HMW chains alongside an increase in the proportion of low molecular weight chains. Significantly, these adjustments resulted in remarkable enhancements in the shear thinning index and strain hardening modulus of the fabricated resins.

show abstract

Effect of blending small amount of high-density polyethylene on molecular entanglements during melt-drawing of ultrahigh-molecular-weight polyethylene

Cited by 9 publications

References 51 publications

Optimal Entanglement of Polymers Promotes the Formation of Highly Oriented Fibers

Optimal Entanglement of Polymers Promotes the Formation of Highly Oriented Fibers

Study on the synergistic effect of additives on the processing performance of UHMWPE/HDPE blends

Splitting for strength: Manipulating polymerization reactor split ratios to control mechanical and rheological properties in bimodal polyethylene resins

Contact Info

Product

Resources

About