Preparation, characterisation and properties of green composites from Pinus roxburghii fibre

Pinus roxburghii needles are plentiful in the Himalayas and may be processed into a natural fibre. In this research, polylactic acid composites were made, including both untreated and treated Pinus roxburghii fibres as reinforcing materials. The Pinus roxburghii fibres were produced by subjecting the Pinus roxburghii needle to an alkali treatment with a 5% sodium hydroxide solution in water, and the Pinus roxburghii fibres were obtained by a water retting extraction method. Pinus roxburghii fibre–polylactic acid composites were made using a compression moulding process. Composites were fabricated utilizing treated and untreated Pinus roxburghii fibre with fibre loadings of 20%, 30%, and 40% by weight. Subsequently, the investigators examined the alterations in the tensile, flexural, impact, and morphological properties with sodium hydroxide treatment. As expected, alkaline treatment considerably boosted the compatibility between Pinus roxburghii fibre and polylactic acid, leading to improvements in the morphological, hardness, and mechanical characteristics of Pinus roxburghii fibre composites. In addition, when 30 wt.% of treated fibres were used, the mechanical characteristics improved.