Fingerprint Recognition Of Polyacrylamide Based On The Condition Of Stratum

Polyacrylamide is a water-soluble macromolecule polymer,of which the anionic Polyacrylamide is widely used in industrial oil displacement of oil field in China.Polyacrylamide can be partially hydrolyzed to produce HPAM by the hydrolysis reaction.The practice shows that HPAM can be used as the polymer to drive oil in the chemical flooding technology,and its effect on enhanced oil recovery is very obvious.It is of great significance to measure the degree of hydrolysis of HPAM,however,the traditional method of measuring the degree of hydrolysis of polymer has many limitations,some of them are not suitable for measuring in the condition of mixed sewage and sediment,and some experimental results show large error,so it is necessary to find a fast and effective method to measure the degree of hydrolysis of HPAM and determine the hydrolysis law of HPAM under condition of stratum.In this paper,the hydrolysis degree of HPAM was determined under different environment by using high-performance liquid chromatography instrument under the condition of detection wavelength of 200 nm,flow rate of 1.0 m L / min,flow phase of9:1 ratio of monopotassium phosphate to methanol.The result as shown below: 1.The relative molecular mass and the addition of low content of Surfactant had no obvious effect on the UV absorption of the amide group,the water used in the blending solution and the different batch production would cause a small fluctuation,the degree of hydrolysis,however,would influence a lot,the higher degree of hydrolysis of the polymer,the lower the UV absorption it would be,and the smaller slope of the standard curve it would form.2.Temperature and p H were the main factors to make the degree of hydrolysis of HPAM increased.The higher the temperature was,the faster the degree of hydrolysis of HPAM increased,and the theoretical limit of the final degree of hydrolysis was also increased.p H determined the shape of growth curve and the hydrolytic mechanism.3.When the solution with different p H at the same temperature,the hydrolysis rate was the slowest under the neutral condition and the second one was under the weak acid condition.Under these two conditions,the relationship between the degree of hydrolysis and the aging time increased almost linearly,and the hydrolysis rate was constant.Under the condition of weak base,the image was a two-segment straight line with varying slope,and the slope of the second segment decreases obviously,the hydrolysis mechanism was between self-acceleration and self-retardation,and more inclined to self-retardation mechanism.Under alkaline condition,the image was hyperbola,which was a typical mechanism of self-retardation reaction.,the hydrolysis rate was inversely proportional to the second power of aging time.The water quality environment and the existence of core sand had limited influence on the degree of hydrolysis and could not play a decisive role.