水溶性ポリマーの原子とメソスケールのシミュレーションをリンクする
Massimo G Noro1, Prem K C Paul, Patrick B Warren
1Unilever Research and Development Port Sunlight, Bebington, Wirral CH63 3JW, UK.
Journal of the American Chemical Society
|June 12, 2003
まとめ
この研究は,ポテンシャル・オブ・メアフォース (PMF) 方法を用いた分子およびメソスコピックポリマーシミュレーションをリンクしています. それは,熱力学的データと一致するようにメソスケールパラメータを校正し,ポリマー吸附行動の正確な予測を可能にします.
科学分野:
- ポリマーサイエンスの科学
- コンピューティング・ケミストリー
- マテリアルサイエンス 材料科学
背景:
- 分子およびメソスコピクシミュレーションのブリッジングは,溶液中のポリマーの振る舞いを理解するために重要です.
- 正確な熱力学パラメータは,予測可能なメソスケールポリマーモデリングに不可欠です.
研究 の 目的:
- 水溶性ポリマーの分子およびメソスコピクシミュレーションをリンクするための堅牢な方法の確立.
- メソスケールシミュレーションを使用して,表面へのポリマー吸収の正確な予測を可能にします.
主な方法:
- 原子学シミュレーションから熱力学数値を導出するために,平均力 (PMF) 方法の潜在力を利用しました.
- 計算された熱力学データ,例えばモノマー第2のビリアル係数などのメソスケールシミュレーションパラメータを調整しました.
- 自己一貫したフィールド理論を応用して,質量と表面の相互作用パラメータ (チーパラメータ) を計算した.
主要な成果:
- 水溶性ポリマーの分子およびメソスコピクシミュレーションレベルを成功裏に結びつけました.
- モノメア吸附イソテルムとビリアル係数の正確な計算が実証されました.
- エチレン酸化物 (EO) とプロピレン酸化物 (PO) が水溶液からシリカに吸収される相互作用パラメータを計算した.
結論:
- 開発された方法は,原子学的データを用いてメソスケールポリマーシミュレーションのパラメータ化のための信頼性の高いアプローチを提供します.
- このテクニックは,水性環境におけるポリマー-表面相互作用のメソスケールシミュレーションの予測力を高めます.
- 発見は,ポリマーコーティングの設計とインターフェース現象の理解に適用できます.
関連する概念動画
03:13Intermolecular Forces
Atoms and molecules interact through bonds (or forces): intramolecular and intermolecular. The forces are electrostatic as they arise from interactions (attractive or repulsive) between charged species (permanent, partial, or temporary charges) and exist with varying strengths between ions, polar, nonpolar, and neutral molecules. The different types of intermolecular forces are ion–dipole, dipole–dipole, hydrogen bonds, and dispersion; among these, dipole–dipole, hydrogen bonds, and dispersion...
02:34Polymers
The word polymer is derived from the Greek words “poly” which means “many” and “mer” which means “parts”. Polymers are long chains of molecules composed of repeating units of smaller molecules, known as monomers. They either occur naturally, such as DNA and proteins, or can be constructed synthetically, like plastics. They have varied structural characteristics, such as linear chains, branched chains, or complex networks, that contribute to the properties that they exhibit. Additionally,...
01:10Polymers: 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.
01:21Polymer Classification: Crystallinity
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
01:08Molecular 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...
01:27Determination 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...