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This paper aims to investigate and prepare the composite polyurea greases with excellent thermal stability and tribological properties.

In this paper, composite Ba-based (Ba, barium) tetra-polyurea lubricating greases were prepared with two different methods: mixing Ba-based gelatinizer and tetra-polyurea gelatinizer by a physical method; and introducing barium carboxylate into tetra-polyurea molecules by a chemical method. The properties of the products, such as heat stability, water resistance and friction performance, were analyzed with thermogravimetry, water-resistance test and four-ball friction test.

The results indicated that the products obtained by chemically introducing barium carboxylate into tetra-urea molecules showed better elevated temperature tribological properties, and the disadvantages of the polyurea greases with high temperature hardening were also obviously improved. The cone penetration rate at 180°C for 24 h is only 3 per cent. The friction coefficient can be decreased to 0.44 and the last non-seizure load value was increased from 560 N to 1,120 N without any other additives.

The research is significant because the prepared composite grease showed excellent performances, such as the outstanding thermal stability, water resistance and excellent extreme pressure and anti-wear properties, which may be widely applied in steel, metallurgy, bearings and other industrial fields.

The purpose of this paper is to study the evolution of Chinese industrial relations after the market reform of 1978, while basing its arguments and conclusion on analysis of the interactions of key actors in the labour arena in China. The significant phenomena in the evolution of industrial relations are the coming of transnational capital and the emergence of self‐organising protests by migrant workers.

The paper uses a case study approach.

The Labour Contract Law and the local political economy experience strong effects from TNCs and other business players. Meanwhile, globalisation has introduced the civil society movement to China, which has given rise to an increasing number of NGOs working for labour rights. Tight financial and technical connections between grassroots NGOs and international donor organisations make it possible for bottom‐up labour activities to counteract the unilateral influence of the state and market over the Chinese workforce. Since the ACFTU, the official trade union umbrella, has many institutional constraints to undertake a thorough transition towards labour in the near future, workers' representation is diversified.

One implication for further theoretical studies is that tripartism cannot fully disclose the reality of Chinese labour, and that labour representation derives from both unions and self‐organisation of workers, such as NGOs, which opens more room for the entrenchment of the grassroots labour movement to sustain the balance of power among the state, ACFTU, firms, international market forces and individual workers in the long term.