Research On Detection System Of Polymer Orientation Degree Based On Ultrasonic

Polymer pipe production monitoring is an important means to ensure thequality and perfoemance of pipe, orientation degree of the molecular chainhas a direct impact on the performance of the pipe. In order to improve theperformance of polymer pipes, detection of the degree of orientation of thepolymer material has become the most important research direction in the fieldof polymer research, and material orientation's real time monitoring in themolding process of the material processing has aroused the attention ofscholars at home and abroad.This paper research on the detection system of polymer orientationdegree based on ultrasonic. Using ultrasonic detector made by IndustrialMaterials Institute of National Research Council Canada and self madeultrasonic detection system to detect the velocity of ultrasonic wave of somepolymer material sample independently.The result shows self made ultrasonicdetection system can implement accurate measurement,the relative error isless than5%,and good repeatability.It proved self made ultrasonic detectionsystem can measure the propagation speed of polymer materials.This paper using DSP based ultrasonic velocity measurement circuit(Longitudinal wave) to detect the velocity in vertical direction ofmolecular orientation of different orientation degree samples. The result showsthat different orientation degree polymer materials have different ultrasonicvelocity in vertical direction of molecular orientation. A mathematicalmodelling has been gotten through infrared dichroic and velocity ofultrasonic,and proved ultrasonic velocity can be used to orientation degreeon line detection.This paper using DSP based ultrasonic velocity measurementcircuit(rayleigh wave) to detect the velocity in axial direction of molecularorientation of different diameter of PVC O pipes. The result shows rayleighwave can be used to detect differnt diameter and orientation degree PVC Opipe,which makes further effort to demonstrate ultrasonic velocity can be usedto orientation degree on line detection.Compared with the experiment data,ultrasonic longitudinal wave isappropriate for single axis and dual axle orientation degree detection,ultrasonic rayleigh wave is appropriate for axial direction orientation degreedetection.