Broadband sound absorption cellulose/basalt fiber composite paper with excellent thermal insulation and hydrophobic properties

Cellulose-based materials find extensive applications in sound absorption due to their high porosity, biodegradability, and cost-effectiveness. However, these materials also suffer from some limitations such as hydrophilicity and low thermal stability that restrict their applicability and lifespan. Herein, we report a cellulose/basalt fiber (CBF) broadband sound absorption composite paper with excellent thermal insulation and hydrophobic properties fabricated by wet forming and silane vapor treatment. Benefiting from the introduction of eco-friendly basalt fibers, the composite paper has an adjusted pore structure and thermal conduction pathway, leading to enhanced sound absorption and thermal insulation performance. Particularly, the composite paper with 50 wt% basalt fiber shows remarkable sound absorption coefficient (0.71 on average) and ultralow thermal conductivity (0.034 W/m·K). As a novel application of eco-friendly materials for sound absorption, the CBF composite paper is an ideal candidate for indoor architectural decoration. •A green composite has been fabricated using cellulosic fiber and basalt fiber.•The composite is a promising lightweight, sound and thermal insulators.•The composite also exhibits excellent hydrophobic and self-cleaning properties.