区块链在以旧换新政策实施中具有重要的潜在价值，在采用区块链前后，针对制造商委托线下零售商以旧换新且在线上渠道直接以旧换新，以及制造商同时委托线上、线下零售商以旧换新两种模式，构建4种双渠道闭环供应链的博弈模型，探讨制造商采用区块链的动机差异。研究发现，无论是否采用区块链，制造商均倾向委托线下零售商以旧换新且在线上渠道直接以旧换新，线下和线上零售商更倾向于制造商同时委托自身以旧换新。当消费者对隐私信息泄露的敏感系数较小且消费者对信息溯源水平的敏感系数较大时，制造商采用区块链可以获得更高的利润，此时线下和线上零售商均会通过“搭便车”获得更高的利润。

Blockchains hold significant potential value in the implementation of trade-in policies, before and after adopting blockchain technology, four game models of dual-channel closed-loop supply chain were constructed considering two modes, where the manufacturer entrusts offline retailer to trade-in and directly trade-in through online channels and entrusts both online and offline retailers to trade-in simultaneously. The difference in motivations for manufacturer to adopt blockchains was explored. It shows that regardless of whether the blockchain is used or not, the manufacturer tends to trade-in directly through online channels. Meanwhile, the offline and online retailers tend to prefer the manufacturer to entrust them to trade-in. When consumers’ sensitivity to privacy information leakage is low and their sensitivity to information traceability levels is high, the manufacturer can achieve higher profits by adopting blockchains, and both the offline and online retailers can benefit from “free riding” at the same time.