Date: 10/11/2021 09:51:56
From: Spiny Norman
ID: 1814268
Subject: Hemp for composites
Hemp fibre looks like a pretty reasonable material to add to composites to improve strength.
Hemp fibre looks like a pretty reasonable material to add to composites to improve strength.
Sorry, hit the wrong button before I finished the post.
Conclusions
• Preliminary characterization of hemp fibers disclosed average length of 76.6 mm, equivalent diameter of 65 μm and density of 1.35 g/cm3.
• Fourier transform infrared (FTIR) results show evidence of hemp fiber molecular interaction with epoxy, which might contribute to mechanical reinforcement.
• A comparison between mechanical properties evaluated by flexural and tensile tests revealed a tendency of epoxy composites with 30 vol% of continuous and aligned hemp fibers to have higher strength and modulus superior to all other investigated composites as well as to plain epoxy and polyester.
• The superior flexural strength (76.7 MPa) and modulus (3.8 GPa) as well as tensile strength (50.5 MPa) and elastic modulus (1.72 GPa) indicated a possible reinforcement effect for 30 vol% hemp fiber in epoxy composites.
• This reinforcement was statistically proved by ANOVA analysis and Tukey tests. On the contrary, the corresponding flexural (49.1 MPa; 1.22 GPa) and tensile (31.5 M P; 0.51 GPa) results for 30 vol% hemp fiber in polyester composites were not statistically supported as a reinforcement effective.
• Scanning electron microscopy fracture analysis of hemp fibers in polyester composites revealed interfacial cracks and decohesion that justify their difficult in providing reinforcement.
Spiny Norman said:
Hemp fibre looks like a pretty reasonable material to add to composites to improve strength.
Hasn’t always?
roughbarked said:
Spiny Norman said:
Hemp fibre looks like a pretty reasonable material to add to composites to improve strength.Hasn’t always?
probably not.
Spiny Norman said:
Sorry, hit the wrong button before I finished the post.Conclusions
• Preliminary characterization of hemp fibers disclosed average length of 76.6 mm, equivalent diameter of 65 μm and density of 1.35 g/cm3.• Fourier transform infrared (FTIR) results show evidence of hemp fiber molecular interaction with epoxy, which might contribute to mechanical reinforcement.
• A comparison between mechanical properties evaluated by flexural and tensile tests revealed a tendency of epoxy composites with 30 vol% of continuous and aligned hemp fibers to have higher strength and modulus superior to all other investigated composites as well as to plain epoxy and polyester.
• The superior flexural strength (76.7 MPa) and modulus (3.8 GPa) as well as tensile strength (50.5 MPa) and elastic modulus (1.72 GPa) indicated a possible reinforcement effect for 30 vol% hemp fiber in epoxy composites.
• This reinforcement was statistically proved by ANOVA analysis and Tukey tests. On the contrary, the corresponding flexural (49.1 MPa; 1.22 GPa) and tensile (31.5 M P; 0.51 GPa) results for 30 vol% hemp fiber in polyester composites were not statistically supported as a reinforcement effective.
• Scanning electron microscopy fracture analysis of hemp fibers in polyester composites revealed interfacial cracks and decohesion that justify their difficult in providing reinforcement.
Looks good.
Hemp has always been one of the strongest and long-lived of natural fibres.