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The purpose of this paper is to deal with the qualitative analysis of hydrodynamic lubrication of asymmetric rollers with non-Newtonian incompressible power law lubricants including Newtonian.

The fluid flow governing equations such as equation of motion along with continuity and thermal equations are solved first analytically and investigated numerically by the Runge-Kutta Fehlberg method.

As a result of this work, it is found that there is a significant change in temperature, pressure, load and traction with Newtonian and non-Newtonian fluids.

The authors considered incompressible hydrodynamic lubrication of two rigid asymmetric rollers, one of them is assumed to be adiabatic. The convection term of the heat flow equation is taken in its average form.

It is a theoretical problem of two heavily loaded rigid cylindrical rollers with cavitations, where the consistency of the power law lubricant is assumed to vary with pressure and the mean film temperature. It has not appeared in the literature.

The purpose of this paper is to develop eco‐friendly coatings based on low‐cost epoxide resins prepared by using a natural phenolic material such as cardanol (non‐toxic), in place of ordinary phenol (toxic), which can be self‐curable at an optimum temperature.

Cardanol‐formaldehyde novolac resins (CNs) were prepared by reacting cardanol with formaldehyde in different molar ratios varying from 1:0.6 to 1:0.9. Prepared CNs were epoxidised by reacting with epichlorohydrin to produce epoxide resins, which would be called as epoxidised CNs (ECNs). Further, ECNs were modified by reacting with diethanolamine (DEtOA), a secondary amine to introduce tertiary amino group(s) into the molecules, required for self‐curability of ECNs. These modified ECNs are referred to as MECNs. The molar ratio of ECNs to DEtOA was taken in accordance with epoxy functionality of epoxide resins (ECNs) which ranged from 0.5 to 2.9. Nine numbers of MECNs (MECN₁ to MECN₉) were prepared by using four epoxide resins. These resins viz. CNs, ECNs and MECNs were characterized by ¹H NMR and FTIR spectroscopic methods for their structure elucidatation, and by gel permeation chromatography for determining their molecular weights.

The most suitable molar ratio of ECN:DEtOA for the preparation of MECNs was found to be 1:1. The CN prepared by using cardanol and formaldehyde in the molar ratio of 1:0.7 was used for the preparation of ECN₂ and MECN₂. Applied films of epoxide resins, designated as MECN₂, had reasonably good physical and chemical resistance properties. With a wide cure window, the films of MECN₂ were found to be self‐curable at an optimum cure schedule of 160°C/30 min. Owing to self‐curability of the developed epoxide resins, the coatings based on them did not require any additional/external crosslinker to be incorporated in the coating composition.

The prepared epoxide resins (MECNs) had good physical and chemical resistance properties, but demonstrated low stability and low resistance to xylene, in particular.

The paper shows how the epoxide resins were prepared by using a low‐cost phenolic material (cardanol) which is obtained from natural renewable resources, instead of petroleum, and is non‐toxic. These developed coatings can be applied as primer coat and top coat on metallic substrates. True self‐curability of the coating films has been achieved via anionic polymerization.