Study On Synthesis And Properties Of Gels Of N-Lauroyl Alanine And Its Amide

Supramolecular gels are gels formed by gel factors with molecular weights less than1000.Due to the unique properties of different gels,the application of gel materials is widespread increasingly.The nature of the gel factor is decisive for the gel,so it is the focus of gel research.There are many types of gel factors.Among them,amino acid gel factors are endowed with good biocompatibility and degradability due to their amino acid structural units,which has attracted the attention of researchers.In this paper,two kinds of gel factors N-Lauroyl-L-alanine（NLLA）and N-Lauroyl-Alanine dodecylamide（N-Lauroyl-L-alanine dodecylamide,NLLAD）are synthesized.The structure of the target product is characterized by infrared spectroscopy,nuclear magnetic resonance spectroscopy,and mass spectrometry,and it is determined that the target product had been synthesized.Two gel factors are used in vegetable oil system,alcohol system,non-ionic surfactant system and non-polar solvent system for gelation research.The minimum gelation concentration（MGC）and phase transition temperature(T_gl)of the gel are studied.The results shows that the NLLAD system gel has a lower MGC value and a higher T_gl value.The fourier transform infrared spectroscopy（FT-IR）pectroscopy and ultraviolet spectroscopy（UV）are used to study the driving force of gel formation,it is concluded that intermolecular hydrogen bonding is the main driving force for gel formation.The X-ray diffraction are used to study the crystal structure inside the gel,the results show that the arrangement of the gel factors in the coagulated solvent differs depending on the solvent,but they are all arranged in layers.The microrheological method is used to study the rheological properties of the gel.The relationship between the mass fraction of the gel factors and the rheological properties of the gel at normal temperature and the relationship between the mass fraction of the gel factor and the thermal stability of the gel at varying temperature are studied.The results show that within a certain concentration range,the mass fraction of the gel factors increases,the rheological properties of the gel increase,the gel formation time becomes shorter,and the gelation speed increases.The microstructure of the gels is observed by polarizing microscope（PLM）,scanning electron microscope（SEM）and transmission electron microscope（TEM）.The three-dimensional network structure that is formed by gel molecules can be observed under three microscopes.In addition,due to different solvents,the properties and applications of gels in different systems are also different.In the vegetable oil system gel,the effect of the types and mass fraction of the gel factors on the oil holding capacity of the oil gel is studied.In the alcohol system gel,the relationship between the mass fraction of gel factors,the types of alcohol and the solvent emission is studied.In the nonionic surfactant system,the emulsion gel that derive from Tween 80system gel and oil gel are prepared,and the rheology and stability of the emulsion gel are tested.For non-polar solvent systems,several kinds of fuel oils are subjected to gelation experiments.Finally,according to the properties of the gel of different systems,the future application directions of the gel of each system are discussed,and trial experiments are carried out,all of which achieved good results.