The report describes the results of experiments, carried out at TRRL, on a proprietary binder, Novophalt. This work was carried out on a repayment basis under the TRRL assessment scheme. Novophalt comprises bitumen modified with polyethylene using a proprietary blending process. The tests to which Novophalt was subjected were designed primarily to assess its potential as a binder for rolled asphalt wearing course material. The introduction of the polyethylene stiffens the bitumen and leads to improvements in laboratory measured values of the resistance to permanent deformation and dynamic stiffness of the mixed material. Asphalt made with Novophalt requires higher manufacturing and compaction temperatures than conventional asphalt. Novophalt binder must be kept stirred to prevent separation of the polyethylene and bitumen. An experiment with Novophalt on a public highway is planned, and this will form the final stage of its assessment. (A)

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