CAJ | 학술논문

利用分子动力学模拟系统研究了不同质量浓度下(1.25％、2.50％、6.06％)聚乙烯唑啉(PEtO)对甲烷水合物的分解作用.模拟体系为甲烷水合物2×2×2的超胞和聚合物对接体系,模拟发现水分子间氢键构架的水合物笼型结构在PEtO的作用下出现扭曲,最终导致水合物笼型结构完全坍塌.通过氧原子径向分布函数、均方位移以及扩散系数比较不同浓度PEtO的作用,证实在一定浓度范围内,PEtO的浓度越高,其水合物分解作用越强.此外,PEtO具有一定的可生物降解性.PEtO对水合物的作用为:PEtO吸附在水合物表面,其中的酰胺基(N-C=O)与成笼的水分子形成氢键,破坏邻近的笼形结构,令水合物分解;PEtO不断分解表面的水合物,直到水合物笼完全分解.
이용분자동역학모의계통연구료불동질량농도하(1.25％、2.50％、6.06％)취을희서람(PEtO)대갑완수합물적분해작용.모의체계위갑완수합물2×2×2적초포화취합물대접체계,모의발현수분자간경건구가적수합물롱형결구재PEtO적작용하출현뉴곡,최종도치수합물롱형결구완전담탑.통과양원자경향분포함수、균방위이이급확산계수비교불동농도PEtO적작용,증실재일정농도범위내,PEtO적농도월고,기수합물분해작용월강.차외,PEtO구유일정적가생물강해성.PEtO대수합물적작용위:PEtO흡부재수합물표면,기중적선알기(N-C=O)여성롱적수분자형성경건,파배린근적롱형결구,령수합물분해;PEtO불단분해표면적수합물,직도수합물롱완전분해.
Molecular dynamics simulations were carried out to study the decomposition of CH4 hydrate in the presence of poly(2-ethyl-2-oxazoline) (PEtO) at different concentrations,including 1.25％,2.50％,and 6.06％ (w,mass fraction).The simulation system was composed of a CH4 hydrate crystal and PEtO,which contained a 2×2×2 supercell of CH4 hydrate crystal and PEtO polymer.System configurations showed that hydrogen bonding networks between water molecules making up the main framework of the hydrate cages were distorted in the presence of the PEtO polymer.Final configurations in all of the systems were completely collapsed.Radial distribution functions of the oxygen atoms,mean square displacements,and diffusion coefficients of water molecules were applied to compare the effect of different PEtO concentrations on the CH4 hydrate.Within a certain concentration range,higher concentrations led to a better inhibition effect.It was confirmed that PEtO is a type of prospective low dosage inhibitor with biodegradability.The decomposition mechanism involves the absorption of the PEtO polymer onto the surface of the hydrate crystal,with its active functional group (N - C=O) forming hydrogen bonds with water molecules in the hydrate and decomposing the hydrate surface.PEtO continued to decompose the surface layer of hydrate,resulting ultimately in the collapse of the hydrate cages.