Related Experiment Video
Updated: Feb 4, 2026

Stereolithographic 3D Printing with Renewable Acrylates
Published on: September 12, 2018
Mechanical Property Improvement of 3D-Printed rPP and vPP through Heat Treatment and Sustainable Filament Reuse
Muralidhara Dagadi1, Jayeshwar Singh1, Adhindra Venkatraman Sridharan1
1School of Engineering, Shiv Nadar Institution of Eminence Deemed to Be University, Gautam Buddha Nagar 201314, India.
Abstract:
This study investigates the mechanical property enhancement of 3D-printed virgin and postconsumer recycled polypropylene (vPP and rPP) structures through systematic heat treatment. ASTM D638 specimens were subjected to cryogenic cooling (0 °C), room temperature, isothermal heating at 60 and 80 °C, and ramped heating between 60 and 110 °C to assess the influence of thermal postprocessing on porosity, tensile strength, and failure mechanisms. Results revealed a consistent decrease in porosity with increasing temperature. Yield strength demonstrated a bell-shaped trend, with maximum yield strength recorded at 60 and 80 °C for vPP and rPP, respectively. Beyond these temperatures, thermal degradation led to a decline in mechanical performance. Ramped heating further enhances stress relaxation and interfacial bonding, improving structural integrity without inducing embrittlement. Heat treatment led to a transition from brittle to ductile failure, while uncertainty analysis validated the repeatability of mechanical behavior, particularly for rPP. This work contributes to the circular economy by enabling the reuse of postconsumer recycled PP in moderately loaded, noncritical components, semistructural applications, or eco-efficient applications where moderate strength is sufficient, thereby reducing environmental impact and material dependency.
Related Concept Videos
Mechanisms of Heat Transfer
Conduction, accounting for approximately 3% of body heat loss at rest, is the process of exchanging heat between molecules of two materials in direct contact. This can result in both heat loss and gain. For instance, when the body is submerged in water, which conducts heat 20 times more effectively than air, it can either lose or gain significant...
Sustainable Development
Mechanism of heat transfer
Mechanisms of Heat Transfer I
Mechanisms of Heat Transfer II
Quantifying Heat

