There is a large world market for manufactured rubber products - the production of natural and synthetic rubbers exceeds 16 million tonnes. Aeronautical and automobile companies (tyres, 'O' rings, hoses, and seals) account for about 60% of the total market. Current methods for estimating cure during the moulding process are unreliable - yet, for a given compound, the final product properties depend on the degree of cure. This project plans to develop an ultrasonic cure monitoring device to operate as a manufacturers' process aid - and more particularly, as an on-line process control tool. Ultrasonic cure monitoring has already been demonstrated by NPL for thermosets, although this technology has yet to be developed commercially. No research has been reported on the use of ultrasonics to monitor the cure of rubber materials. During the exploratory phase, the project will initially investigate the feasibility of using ultrasonic cure monitoring over a wide range of rubber materials and operating conditions. If the technique is proven sufficiently sensitive, the project will move on to the development of two prototype cure meters as a Stage 2 Co-operative Project. Two distinct forms of instrumentation are envisaged; a portable instrument for product testing (at ambient temperature), and an on-line, high temperature instrument for manufacturing, and monitoring process control. Innovative solutions are required to make this project successful, including: high temperature ultrasonic probe design/assembly, real time signal processing, and correlation between ultrasonic cure measurements and current laboratory rheology techniques. The consortium comprises H W Wallace (a SME specialising in instrumentation for the rubber industry), two rubber component manufacturers (end users) to evaluate the instrumentation, MAC (an Irish company) specialising in electronics development and the polymer processing group at the National Physical Laboratory (the RTD performer specialising in the measurement of polymer properties). A specialist ultrasonic transducer manufacturer will be sought during the feasibility stage. The two rubber component manufacturers identified (in Germany and France - the largest European consumer states) will be included after the feasibility stage - their input is not required until the technique can be proved promising; H W Wallace has representation and customers in all member states of the EU.