Binary blends of ethylene vinyl alcohol copolymers, containing 62 (EVOH‐62) and 71 (EVOH‐71) mole percent vinyl alcohols, with nylons (nylon‐6, nylon‐6/12, and nylon‐12) have been prepared from melt mixing in a twin screw compounding machine. Morphological, thermal, rheological, and mechanical properties were determined. EVOH‐62/nylon‐6 and EVOH‐71/nylon‐6 blends showed homogeneous phase morphologies in the nylon‐6‐rich region, and fine phase separations (c.a. 2 × 10−7 m) in the EVOH‐rich region. Melting point depression, positive deviations in viscosity and flexural modulus, and negative deviation in impact strength from the simple additive rule were generally observed. And the results were possibly interpreted in terms of compatibility and increased nylon/EVOH interactions over the nylon/nylon interactions. On the contrary, clean phase separations in large domains were observed from EVOH‐71/nylon‐6/12 and EVOH‐71 /nylon‐12 blends. Fibrillation was also obtained from EVOH rich blends. Probably due to the incompatible nature of these blends, yield at low rate of shear and a mechanical property drop were also observed.

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As a common description of the compaction process, density versus number of roller passes (coverage) is often found in the literature and is subsequently used in the field. The closed formula is introduced to quantify such a relationship. Variables considered are compaction density, mix viscosity, temperature, frequency, and amplitude, in addition to the number of roller passes. Their effects are included in the proposed formula. The experimental data found in the literature are used to verify the equation. Excellent prediction of the data confirms the success of the formulation. As the result of this mathematical modeling, the minimum number of passes required to finish a certain compaction job and the maximum compaction density achievable by a certain compaction operation are suggested. The equation and its features will be an effective tool for using rolling compaction in an effort to construct better roadway pavements.

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