Multi-parameter optimization (grey relational analysis) and modeling of a cellulosic plant/glass fiber hybrid reinforced polymer composite (P x G y E z ) for offshore pressure vessels development

Abstract

The aim of this research is to produce more environmentally friendly materials for offshore applications. Due to their high water absorption, cellulosic fibers are known to be hydrophilic, making composites reinforced with them perform poorly and unreliable in humid settings. Previous research has focused on the development of natural fiber-based composite materials, but none has focused on the optimization of these cellulosic-based fiber-reinforced composites for offshore applications where weight, water absorption, and strength are important considerations. This paper presents the optimization of the composite material P x G y E z (with x, y, and z representing the volume fraction of pineapple leaf fiber (PALF) (P), the volume fraction of glass fiber (G), and fiber length respectively in an epoxy matrix) using the grey relational analysis for offshore pressure vessels. The material at 10% PALF, 15% glass fiber, and 15 mm fiber length, which is, P10G15E15 was the optimum, having a grey relational grade of 0.716. Also, statistical analysis showed that the treated PALF fibers contributed 45.73% to the water absorption properties of the P x G y E z composites as compared to the 0.3% contribution of glass fiber to the grey relational grade and a 9.5% contribution of fiber length. Also, there was an improvement in the grey relational grade by 73.61%. SEM and Fourier-transform infrared spectroscopy (FTIR) analysis showed microstructural and chemical formations that explained the water absorption behavior of the optimized hybrid composite. Also, regression analysis was carried out and an equation was developed for the prediction of grey relational grades at different combinations of P x G y E z . A thick pressure vessel developed with the optimized material was simulated and results showed operational reliability with its yield starting at 30.01 MPa, which is 44.98% higher than the 20.7 MPa limit by the ASME X Class I cylinders.