the development of polymer matrix nanocomposites incorporating copper nanoparticles (Cu-NPs) through UV-photopolymerization additive manufacturing. The research primarily focused on assessing the impact of Cu-NPs on the mechanical properties of these nanocomposites.
Nanocomposites have gained significant attention for their superior mechanical, thermal, and electrical properties compared to traditional materials. Integrating nanoparticles into polymer matrices can significantly enhance performance, making these materials ideal for aerospace, automotive, and biomedical applications.
Copper nanoparticles are known for their excellent electrical conductivity and antimicrobial properties, making them attractive for photopolymer resins. However, challenges such as particle agglomeration and increased viscosity must be addressed to fully leverage these benefits.
study on polymer matrix nanocomposites with copper nanoparticles:
Fabricated and characterized polymer matrix nanocomposites with varying concentrations of Cu-NPs (0.0%, 0.5%, and 1.0% by weight).
Assessed the impact of Cu-NP loading on material properties.
Material Preparation and Characterization:
Photopolymer resin was mixed with Cu-NPs and analyzed using Scanning Electron Microscopy (SEM), revealing a mean particle size of approximately 72.9 nm.
The addition of Cu-NPs increased resin viscosity from 0.4 Pa.s (neat resin) to 1.8 Pa.s (1.0% Cu-NPs formulation).
Mechanical Testing:
Tensile tests were conducted according to ASTM standards on dog-bone shaped samples cured under UV light for 10 minutes.
Weibull statistics were used to assess variability in tensile strength, indicating the reliability and consistency of the materials.
Shrinkage tests measured dimensional stability in the x, y, and z directions during curing.
Results - Tensile Strength:
Incorporating Cu-NPs decreased tensile strength due to nanoparticles acting as stress concentrators.
The neat resin exhibited higher tensile strength compared to Cu-NP formulations.
UV curing enhanced the strength of nanocomposites, underscoring its importance in final mechanical properties.
Results - Modulus and Variability:
Weibull analysis showed high modulus values for both neat resin (34.8) and 1.0% Cu-NP formulation (30.9), indicating low variability in tensile strength and consistent material performance.
Low variability is advantageous for manufacturing, suggesting predictable performance characteristics.
Challenges - Particle Agglomeration:
Cu-NPs showed a tendency to agglomerate and precipitate, causing defects that could lead to fractures in printed parts.
Suggested solutions include using dispersion emulsifiers to suspend nanoparticles and improve their interaction with the resin.
Recommended pre-processing techniques like chemical treatment or heating of Cu-NPs to enhance adhesion and reduce agglomeration.
Shrinkage and Dimensional Stability:
Cu-NP formulations experienced less shrinkage compared to the neat resin, beneficial for maintaining dimensional accuracy.
Shrinkage was minimally affected by curing time (5 vs. 10 minutes), indicating that initial 5 minutes of curing are sufficient for stability.
Conclusion:
The study demonstrated the fabrication of polymer matrix nanocomposites with Cu-NPs using UV-photopolymerization additive manufacturing.
While Cu-NPs reduced tensile strength, UV curing improved the mechanical properties.
Highlighted challenges like particle agglomeration and increased viscosity, with proposed solutions to enhance the manufacturing process.
Emphasized the need for optimized processing techniques to achieve superior nanocomposite materials, with potential applications in various industries.
Significance:
Contributes valuable insights into the potential of nanocomposites to improve material performance in additive manufacturing.