Dominant Effects of Short-Chain Branching on the Initial Stage of Nucleation and Formation of Tie Chains for Bimodal Polyethylene as Revealed by Molecular Dynamics Simulation
Abstract
:1. Introduction
2. Models and Methods
3. Results and Discussion
3.1. Induction Time of Precursor Formation
3.2. The Transformation of Precursors to Stable Nuclei
3.3. Crystal Structures
3.4. Tie Chains
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Conflicts of Interest
Abbreviations
SCB | Short-chain branching |
MSL | Methylene sequence length |
SCBD | Short-chain branching distribution |
BPE | Bimodal polyethylene |
PE | Polyethylene |
MWD | Molecular weight distribution |
MD | Molecular dynamics |
ADMET | Acyclic diene metathesis |
HDPE | High-density polyethylene |
SOP | Site order parameter |
Xc | Crystallinity |
ICF | Interchain contact fraction |
tp* | Induction time |
LCP | Long-chain proportion |
tn* | Formation time of the first stable nucleus |
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Complex BPE Model | Branch | Branch Content (SCB/1000 Backbone Carbons) | Methylene Sequence Length (CH2) | Total Number of CH2 |
---|---|---|---|---|
HDPE | None | 0 | - | 20,000 |
Lb/10S-C2-1 | Ethyl | 1 | 476 | 20,036 |
L/10Sb-C2-1 | Ethyl | 1 | 334 | 20,060 |
Lb/10S-C2-2 | Ethyl | 2 | 244 | 20,084 |
L/10Sb-C2-2 | Ethyl | 2 | 200 | 20,080 |
Lb/10S-C2-3 | Ethyl | 3 | 164 | 20,124 |
L/10Sb-C2-3 | Ethyl | 3 | 142 | 20,060 |
Lb/10S-C2-4 | Ethyl | 4 | 124 | 20,204 |
L/10Sb-C2-4 | Ethyl | 4 | 112 | 20,240 |
Lb/10S-C2-5 | Ethyl | 5 | 100 | 20,300 |
L/10Sb-C2-5 | Ethyl | 5 | 92 | 20,320 |
Lb/10S-C2-6 | Ethyl | 6 | 82 | 20,162 |
L/10Sb-C2-6 | Ethyl | 6 | 76 | 20,120 |
Lb/10S-C2-7 | Ethyl | 7 | 70 | 20,150 |
L/10Sb-C2-7 | Ethyl | 7 | 66 | 20,180 |
Lb/10S-C2-8 | Ethyl | 8 | 62 | 20,302 |
L/10Sb-C2-8 | Ethyl | 8 | 58 | 20,180 |
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Hu, Y.; Shao, Y.; Liu, Z.; He, X.; Liu, B. Dominant Effects of Short-Chain Branching on the Initial Stage of Nucleation and Formation of Tie Chains for Bimodal Polyethylene as Revealed by Molecular Dynamics Simulation. Polymers 2019, 11, 1840. https://doi.org/10.3390/polym11111840
Hu Y, Shao Y, Liu Z, He X, Liu B. Dominant Effects of Short-Chain Branching on the Initial Stage of Nucleation and Formation of Tie Chains for Bimodal Polyethylene as Revealed by Molecular Dynamics Simulation. Polymers. 2019; 11(11):1840. https://doi.org/10.3390/polym11111840
Chicago/Turabian StyleHu, Yanling, Yunqi Shao, Zhen Liu, Xuelian He, and Boping Liu. 2019. "Dominant Effects of Short-Chain Branching on the Initial Stage of Nucleation and Formation of Tie Chains for Bimodal Polyethylene as Revealed by Molecular Dynamics Simulation" Polymers 11, no. 11: 1840. https://doi.org/10.3390/polym11111840