Understanding the Influence of Manufacturing and Material Parameters on the Mechanical Properties of Polymer-Clay Composites: An Exploratory Statistical Analysis

This paper analyses a set of previously obtained experimental results on various clay fillers added to high density polyethylene (HDPE). The composite material was compounded using an extrusion process and manufactured into tensile test samples by means of hot pressing. Various manufacturing parameters (number of extrusions, press time, sample cooling method), material (polymer grade, clay type, clay weight loading) and testing parameters (strain rate) were investigated to determine their influence on the mechanical properties of the composite system.

Exploratory data analysis was first employed by graphically representing the data using scatter plots to identify any main characteristics, patterns or anomalies. The statistical analysis was used to quantify the effects of the ultimate tensile strength by first conducting a one way ANOVA analysis before developing a linear model for the response variable analysis. For the percentage elongation to failure, the observations was first grouped into three groups, Brittle, Intermediate or Ductile. A linear discriminant analysis was performed to classify the groups considering a training set of 80% randomly selected observations and testing on the remaining 20%.