Abstract: Taking a two-tier supply chain composed of a supplier and a manufacturer as the research object, this paper explores the impact of blockchain technology on low-carbon technology sharing strategies within the supply chain. By introducing the time factor, differential game models are constructed for six scenarios: scenarios without incentive contracts, with cost-sharing contracts, and with revenue-sharing contracts, both before and after blockchain implementation. A comparative analysis reveals that before blockchain implementation, the level of low-carbon technology sharing effort by both the supplier and the manufacturer under a cost-sharing contract is higher than that under no incentive contract, while the implementation of a revenue-sharing contract depends on the proportion of revenue shared by the manufacturer with the supplier. Furthermore, given determined cost-sharing and revenue-sharing ratios, the manufacturers selling price after blockchain implementation is higher than before under any contract type. The selling price under a cost-sharing contract is the same as that under no incentive contract. When the blockchain cost exceeds a certain threshold, the selling price under a revenue-sharing contract is higher than under the other two contracts; otherwise, it is lower. The study also finds that with appropriate blockchain usage costs, a cost-sharing contract can enhance the level of low-carbon technology sharing in the supply chain without affecting the manufacturer's selling price or the level of sharing effort. However, if the blockchain usage cost is too high, it may instead reduce the supply chain's technology sharing level.

Key words: blockchain, contract coordination, differential game, low-carbon technology sharing, low-carbon supply chain