Effect of-volume fraction of ramie cloth on physical and mechanical properties of ramie cloth/LTP resin composite

Ramie cloth/UP resin composite was formed at 0.2 MPa and cured at room temperature for 24 h and treated at 80 degrees C for 2 h. The physical and mechanical properties of the composites with different volume fractions of ramie cloth were studied. The results show that, with the increase of the volume fraction of the ramie cloth, densities of the composites become greater and greater, though all lower than the theoretical values, the linear shrinkage during the formation decreases from 1.20% of the original UP resin to 0.18% of the composite with 30% of ramie cloth in volume, all the composites also absorb more water than UP resin casting, greater volume fraction of the fiber, more water will be absorbed, but the increase in water absorption becomes smaller and smaller with time. As regards some mechanical properties, the tensile strength, flexural strength, flexural modulus and impact strength are all improved when more ramie fiber is added. Compared with those of pure UP resin casting, the mechanical properties are increased by 93.93%, 76.20%, 190.18% and 227.26% respectively when the volume fraction of the ramie cloth in the composite is 30%. The differential scanning calorimetry results show that only one peak will appear for the sample without or with less ramie fiber while two peaks will appear when more ramie cloth is added.