Green material product demand analysis: A theory of planned behavior model incorporating environmental knowledge factors

Promoting the consumption of products made from green materials is a crucial strategy for achieving clean production. However, there is often a misalignment between green materials and the product design, leading to suboptimal applications. Conducting consumer demand analysis for green-material-based products and pursuing demand-driven green product development can enhance the recognition of these materials, which is essential for sustainable consumption. The theory of planned behavior (TPB) is frequently employed to analyze consumer demand by examining factors such as behavioral intentions and attitudes. However, the current TPB model does not consider consumers’ environmental awareness and knowledge, limiting its effectiveness in predicting green consumption behavior. To address this limitation, this study proposes the introduction of environmental knowledge factors into the classic TPB model, constructing a theoretical framework to analyze factors affecting consumers’ willingness to purchase green products, and applying it to green product demand analysis. A case study was conducted using the application of polylactic acid (PLA) materials in clothing to validate this model. Specifically, (1) an online survey of 433 consumers was conducted to test both the classical TPB model and the extended TPB model using structural equation modeling and (2) two garments made from polylactic acid (PLA) material were designed and evaluated through consumer experience assessments. The findings indicate that attitude and environmental knowledge positively affect consumers’ willingness to purchase garments made from PLA material, with environmental knowledge positively moderating the relationship between attitude and purchase intention. The extended TPB model demonstrated higher predictability than the classical TPB. In addition, the garment made from PLA material designed based on the extended TPB received higher ratings in the consumer evaluations, suggesting that the TPB model incorporating environmental knowledge factors is more effective for studying consumer demand. This study provides a methodological reference for green product demand analysis, aiding in the design and development of green products, and promoting clean production and sustainable consumption.