The invention relates to the technical field of on-line analysis, in particular to a
polyvinyl alcohol alcoholysis
degree distribution on-line measurement method and
system.The method comprises the following steps that
spectral data of a
polyvinyl alcohol solution is obtained, a characteristic absorption
wave band in the ester group to hydroxyl
group process is extracted, absorption intensity in the
wave band is recorded to construct a sequence, peak positions are extracted, intensity difference is calculated, and the direction is marked; and identifying a fluctuation interval, calculating an
angular velocity trend, and screening anomalies and generating an unstable section set in combination with a disturbance amplitude and a component
coincidence rate. According to the method, quantitative analysis of alcoholysis degree conversion characteristics is realized through selection of characteristic absorption wavebands in
spectral data and accurate identification of the change trend of the intensity difference values, the characterization precision of the alcoholysis degree of
polyvinyl alcohol is improved, and more accurate trend fluctuation identification capability is provided through comparison of
angular velocity difference values of absorption
intensity change rates, so that the accuracy of the analysis of the alcoholysis degree of polyvinyl
alcohol is improved. The analysis level of alcoholysis
degree distribution details is remarkably improved, the abnormal fluctuation interval of alcoholysis degree component distribution is recognized, and the product quality difference caused by alcoholysis degree fluctuation is reduced.