共沉淀法制备纤维素/天然橡胶薄膜及其性能研究

Study on the Preparation and Properties of Cellulose/Natural Rubber Films via Co-precipitation Method

天然橡胶(NR)是一种重要的战略资源,但是其本身力学性能可能无法完全满足应用需求,往往需要使用补强剂对其进行改性。而传统的橡胶工艺严重依赖以石油为基础的材料,如炭黑(CB),对环境污染严重,不利于浅色制品的应用。为响应绿色环保的主题,减轻环境污染,选取绿色可再生的纤维素作为浅色橡胶制品的补强剂是一个应用前景广阔的技术方案。纤维素与天然橡胶的相容性决定了改性材料的性能。本研究使用羟乙基纤维素(HEC)、羧甲基纤维素钠(CMC)和纳米纤维素(CNF)为原料,对天然橡胶薄膜进行改性,旨在显著提升其综合性能。通过对复合薄膜材料进行FT-IR、XPS、力学性能、交联密度、硬度、接触角等表征测试,研究结果表明,这三种纤维素均可以提高天然橡胶的交联密度,HEC对天然橡胶的交联密度提升最大,可达到3.33倍。此外,纤维素与天然橡胶之间形成的氢键连接,对天然橡胶薄膜的力学性能起到了关键作用。HEC/NR复合薄膜的拉伸强度最大,达到36.17 MPa,断裂伸长率达2138.78%。纤维素的加入显著提高了复合薄膜的亲水性,这主要归功于纤维素分子中丰富的羟基。这一发现为改善天然橡胶制品的润湿性和加工性提供了新思路,也为复合薄膜材料在多个领域的应用开辟新的可能性。

Natural rubber(NR)is a crucial strategic resource;however,its inherent mechanical properties may not fully meet the demands of certain applications,often necessitating reinforcing agents for modification.Traditional rubber processing heavily relies on petroleum-based materials,such as carbon black(CB),which poses significant environmental pollution and is unsuitable for light-colored products.To address environmental sustainability and reduce pollution,employing green and renewable cellulose as a reinforcing agent for light-colored rubber products presents a promising technological solution.The compatibility between cellulose and natural rubber determines the performance of the modified material.In this study,hydroxyethyl cellulose(HEC),sodium carboxymethyl cellulose(CMC),and nanocellulose(CNF)were utilized as raw materials to modify natural rubber films,aiming to significantly enhance their overall properties.Characterizations of the composite film materials through FT-IR,XPS,mechanical properties,crosslink density,hardness,and contact angle tests reveal that all three types of cellulose can increase the crosslink density of natural rubber,with HEC showing the highest improvement,achieving an increase by a factor of 3.33.Additionally,the hydrogen bonding formed between cellulose and natural rubber plays a critical role in the mechanical properties of the natural rubber films.The tensile strength of the HEC/NR composite film reached a maximum of 36.17 MPa,with an elongation at break of 2138.78%.The incorporation of cellulose significantly enhanced the hydrophilicity of the composite films,primarily attributed to the abundant hydroxyl groups in the cellulose molecules.This finding provides a novel approach to improving the wettability and processability of natural rubber products and opens new possibilities for the application of composite film materials across various fields.