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幻象力量平衡程序用于预测纠的聚合物网络的模块
Tim Bernhard1,2, Andrei A Gusev2
1Laboratory for Nanometallurgy, Department of Materials, ETH Zürich, 8093 Zürich, Switzerland.
ACS polymers Au
|October 13, 2025
概括
一种新的计算方法使用最小的资源准确地预测了聚合物网络剪切模量. 这种方法为材料科学的传统模拟方法提供了更快,更具成本效益的替代方案.
科学领域:
- 聚合物科学 聚合物科学
- 计算材料科学科学 计算材料科学
- 类风病学 类风病学 类风病学
背景情况:
- 预测纠的聚合物网络的剪切模量对于材料设计至关重要.
- 像分子动力学 (MD) 模拟这样的现有方法是计算密集的.
- 理论模型可能无法准确地捕捉复杂的网络架构.
研究的目的:
- 为了呈现一个新的计算幻影力量平衡,最大热同质化程序 (FB-MEHP).
- 为了有效地预测纠的聚合物网络的平衡剪切模量.
- 根据已建立的模拟和理论方法验证FB-MEHP.
主要方法:
- 使用蒙特卡洛方法生成珠弹聚合物网络微结构.
- 通过在相邻的网络链之间创建四功能交叉链接来引入纠.
- 优化微结构到它们的最小自由能量状态,用于模量计算.
主要成果:
- FB-MEHP与压力放松MD模拟和米勒-马科斯科理论 (MMT) 几乎完全一致.
- FB-MEHP所需的计算资源明显低于MD模拟 (比MD模拟少4个数量级).
- 该程序与各种聚合物网络的实验数据有很好的一致性,包括瓶和状结构.
结论:
- FB-MEHP是一种计算效率高,准确的方法,用于预测聚合物网络剪切模量.
- 这种程序为预测各种聚合物网络架构的模量提供了一个实用的工具.
- 在设计和优化聚合物基材料方面,FB-MEHP具有潜在的应用.
相关概念视频
Polymers: Defining Molecular Weight
Unlike small molecules with definite molecular weights, polymers are a mixture of individual polymer chains of varying lengths, each with a unique molecular weight. So, the molecular weight of a polymer is expressed as an average value based on the average size of the polymer chains. The two most common forms of averages used for polymers are the number average molecular weight and weight average molecular weight.
The number average molecular weight (Mn) is the summation of the number...
The number average molecular weight (Mn) is the summation of the number...
Polymers: Molecular Weight Distribution
For any given polymer, the weight average molecular weight (Mw) is higher than, if not equal to, the number average molecular weight (Mn). The only situation in which the weight average molecular weight and the number average molecular weight are equal is when a polymer consists only of chains with equal molecular weight. However, this never happens in a synthetic polymer, since it is difficult to control the polymerization process up to a molecular level with accuracy to a hundred percent.
Anionic Chain-Growth Polymerization: Mechanism
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael acceptor.
Molecular Weight of Step-Growth Polymers
Step growth polymerization involves bi or multifunctional monomers. Bifunctional monomers react to form linear step growth polymers, whereas multifunctional monomers react to form non-linear or branched polymers.
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
Determination of Molar Masses of Polymers I
Polymerization produces macromolecules with a range of chain lengths due to the random nature of molecular growth processes. As chains form and terminate at different stages, a single polymer sample contains molecules of varying sizes rather than a uniform structure. This variability is described using average molar masses and distribution-related parameters, which together provide a comprehensive understanding of polymer characteristics.The distribution of molar masses plays a critical role in...
Determination of Molar Masses of Polymers II
Polymer samples typically consist of macromolecular chains with a distribution of lengths, resulting in a range of molar masses rather than a single discrete value. Conventional descriptors such as the number-average molar mass and weight-average molar mass quantify this distribution but do not fully capture polymer behavior in solution..The viscosity-average molar mass provides a more realistic description of polymer behavior in solution because it accounts for the enhanced contribution of...

