Laboratory Studies of Termite Resistance V. The Termite Resistance of Plastics,
Abstract
An account is given of a series of laboratory tests to determine (I) the resistance to termite attack of various plastics. (ii) the factors affecting such resistance, and (iii) methods of improving resistance of those plastics shown to be susceptible to attack. The plastics in common use vary widely in susceptibility to attack and range from highly resistant materials such as nylon, phenolic laminates, and epoxy and polyester resins to readily damaged materials such as plasticized polyvinyl chloride, low-density polyethylene, and cellulose esters. The nature of the surface finish is unimportant in relation to termite attack. An increase in thickness of plastic films or foils has been shown to reduce the susceptibility to attack but the reason is not evident. In some materials hardness appears to be important. This has been observed in studies with materials such as polyvinyl chloride or cellulose acetate with different amounts of plasticizer, and also in polyethylenes of different density. Polyethylene also shows increasing termite resistance as molecular weight increases and melt flow index decreases. There are indications that susceptibility is also influenced by the choice of plasticizer as polyvinyl chloride plasticized with tricresyl phosphate is significantly less susceptible than when plasticized with dioctyl phthalate. The amount of attack on susceptible plastics may be reduced by the addition of small quantities of any of several insecticides, of which the best appear to be aldrin and dieldrin. Possible hazards involved in the widespread use of plastics with such additions require further investigation. A significant reduction in damage to susceptible plastics materials has been achieved by the addition of a small volume of a non-toxic mineral tiller such as hard silica or zircon flour, but practical application is limited by processing difficulties.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1969
- Accession Number
- ADA305576
Entities
People
- A. H. Wetherly
- F. J. Gay