大理白族彩绘的材料特性与耐久机理——基于成分数据的界面反应研究

Material Properties and Durability Mechanisms of Bai Ethnic Polychrome in Dali—A Study on Interfacial Reactions Based on Compositional Data

摘要: 大理白族彩绘以其不起皮、不掉落的耐久性著称，而学界对其特殊耐久性的材料学机理仍缺乏系统认知。本文总结前人研究成果，对彩绘颜料层与地仗层的成分数据进行系统再分析，深入探讨天然原料与墙面材料间的界面反应机理。整理已有数据发现：彩绘颜料层以多种天然矿物颜料为主，辅以传统胶结材料构成；墙皮由糯米浆、麻纤维等物质组成。颜料墙皮二者之间发生“碳化–钙矾石协同固化”反应——石灰碳化生成方解石并与活性硅铝形成C-S-H凝胶，天然原料中的植物胶通过钙离子桥接形成柔性锚固层，从而有效抑制起皮脱落。本文通过对比天然原料与丙烯酸乳液等合成材料的成分数据，进一步探究天然材料耐久更好的机理。本研究可为大理白族彩绘的科学保护与修复提供理论依据。

Abstract: Dali Bai ethnic polychromy is renowned for its exceptional durability, exhibiting almost no peeling or detachment over time. However, the material science mechanisms underlying this unique longevity remain insufficiently understood in academic research. This paper synthesizes previous studies and systematically reanalyzes compositional data from both the pigment layer and the ground layer of the paintings, aiming to investigate the interfacial reaction mechanisms between natural raw materials and wall substrates. The results indicate that the pigment layer is primarily composed of various natural mineral pigments combined with traditional binders, while the plaster layer consists of glutinous rice paste, hemp fibers, and other components. A synergistic curing reaction—referred to as “carbonation-ettringite collaborative stabilization”—occurs between the pigment and plaster layers: lime carbonates to form calcite, which reacts with reactive silica and alumina to generate C-S-H gels; simultaneously, plant-based glues in natural materials form flexible anchoring layers via calcium ion bridging, effectively inhibiting peeling and detachment. By comparing compositional data of natural materials with synthetic alternatives such as acrylic emulsions, this study further explores why natural materials exhibit superior durability. The findings provide a theoretical basis for the scientific conservation and restoration of Dali Bai ethnic polychromy.