关键词: 绿色供应链, 双边资金约束, 融资组合策略, 产品绿色度

Abstract: With the continuous expansion of human social production activities and the increasing scale of resources consumption, the challenges of resources scarcity and ecological environment degradation are becoming increasingly prominent. How to reduce the environmental hazards of production and improve the utilization of resources has become a hot topic. To tackle the environmental damage and resources utilization dilemma caused by production activities, green supply chain has emerged. However, the development of China’s green supply chain is still in its primary stage, so producers need to invest more money than they do if they produce manufacturing traditional products and will face the problem of capital constraints. Retailers need to spend a lot of money ordering a large quantity of green products of high prices and also will face the problem of capital constraints. Thus, limited capital restricts the advancement of small and medium-sized producers and retailers in sustainable supply chains. In order to solve capital constraints, green producers and retailers can take three financing portfolio strategies, the financing portfolio strategy of advanced payment and bank loan, delayed payment and bank loan, and sight payment and bank loan. Different financing portfolio strategies will have different effects on their respective earnings and enthusiasm to produce and sell green products. Therefore, this paper focuses on the financing dilemma faced by both producers and retailers in green production due to financial constraints, aiming to address the following three core issues: (1)Is there any bankruptcy risk for producers and retailers? If so, what are the conditions to trigger the bankruptcy risk? Can banks, as lenders, achieve the balance between income and expenditure? (2)What is the impact of changes in bank loan interest rate on product greenness, producer’s profits and retailer’s profits? (3)How will the different loan interest rates given by banks to producers and retailers affect the choice of financing portfolio strategy? Through the above analysis, it will not only offer a great help for producers and retailers to make optimal financing portfolio decisions, but also significantly promote the efficient development of green supply chain.
Focusing on the bilateral capital constraints problem of producers and retailers in green supply chain, this paper takes the two-echelon green supply chain comprised of a single producer and a single retailer as the research object. This paper proposes three financing portfolio strategies: (1)Financing portfolio strategy of advanced payment and bank loan (AF strategy). In this strategy the retailer initiates loans from banks and pays the producer in advance. (2)Financing portfolio strategy of deferred payment and bank loan (DF strategy). In this strategy the producer initiates loans from banks and allows the retailer to defer payment. (3)Financing portfolio strategy of sight payment and bank loan (IF strategy). In this strategy the producer and retailer jointly initiate loans from banks and make sight payment for goods. No matter which strategy is adopted, the producer and retailer will both face financing risks. Considering the financing risks, this paper constructs Stackelberg models to analyze the optimal decision-making for producers and retailers, as well as the conditions under which the bank can achieve balanced budgets. It also deeply explores the impact of interest rate variations on the choice of financing portfolio strategies of the producer and retailer, analyzes it and draws some valuable implications. In order to verify the inferences, numerical simulation is performed by MATLAB software.
Through the research on the financing portfolio strategy of the producer and retailer with bilateral capital constraints, the specific research results are as follows. For the bank, it will be profitable only if the producer chooses the deferred payment and bank loan financing portfolio strategy, and its revenues from sales of green products are not sufficient to repay the loan principal. The difference in loan interest rates between the producer and retailer, r₁ andr₂, will significantly affect their selection of financing strategy options: whenr₁≥r₂ , the equilibrium strategy will choose the DF strategy; when r₁>r₂, the strategy choice will depend on the relative scale of the equilibrium interest rate r^*, and the loan rates of both parties, showing phased characteristics: (1)when r₁>r₂≥r^*, the producer and retailer have different strategy preferences, and there is no equilibrium strategy that satisfies both parties; (2)when r₁>r^*>r₂, the equilibrium strategy will choose the AF strategy.
This study explores the field of green supply chain financing, focusing on addressing the financing strategy challenges faced by upstream and downstream enterprises under bilateral capital constraints, and proposes targeted financing portfolio solutions. Of course, there are still some limitations in this study. For example, this paper only analyzes and studies the financing strategy when the market demand for green products is determined. In the future, we can also study capital constraints in green supply chain based on uncertain market demand. Besides, government subsidies and other helpful policies can also be taken into consideration.

Key words: green supply chain, bilateral capital constraints, financing portfolio strategies, product greenness