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This study focused on the physical properties of latex extracted from five species of Artocarpus J.R.Forster & G.Forster, namely: A. altilis (Parkinson) Fosberg, A. blancoi Merr, A. camansi Blanco, A. heterophyllus Lam., and A. ovatus Blanco as potential natural adhesives. Surface morphology showed that all five Artocarpus spp. have no specific forms, but otherwise flexible and viscoelastic. Contact angle measurements showed that all samples of Artocarpus spp. were hydrophilic with low contact angle values owing to the contents of natural source of the latex. FTIR analysis matched all Artocarpus latex samples to that of Polyvinyl acetate. Highest resin content was found on A. ovatus with all the species containing natural resin. It was also confirmed that out of the three stress strain analyses, A. camansi had the highest values for tensile strength, A. ovatus had the highest values for Young’s modulus of elasticity and the highest percentage elongation values belonged to A. heterophyllus. Adhesive shear strengths with maximum force values were highest in A. ovatus. Through cluster analysis, out of the eight variables tested A. heterophyllus was the outgroup being attributed to its latex gum-like property. All the above tests and analyses suggested that latex of all five Artocarpus spp. were similar in characteristics to polymer adhesive. Among which A. camansi and A. ovatus exhibited high results on adhesive strength tests.

A support vector machine classification algorithm was formulated to differentiate rubber cup coagulum according to the type of acid coagulant used. Two classification models were established, a binary classification algorithm and a model that can identify if formic, acetic, sulfuric acid, or no acid was used to induce coagulation. The models were based on the properties of the rubber cup coagulum that are easy to measure, such as tensile strength, water contact angle, and density. The binary classification model, which differentiates the industry-accepted formic acid-coagulated rubber cup coagulum from those which are not, exhibited satisfactory reliability, as evidenced by a 92% overall prediction accuracy and 71.4% cross-validation accuracy. Moreover, it was also determined that the rubber properties density, and water contact angle were important contributors for the classification. Acid-induced rubber coagulation is an important post-harvest process that influences the resulting rubber quality. Thus, the accurate differentiation of the rubber samples is useful for quality assurance purposes, as well as in policy enforcement.