Fabrication of 3D Printed Polylactic Acid/Polycaprolactone Nanocomposites with Favorable Thermo-Responsive Cyclic Shape Memory Effects, and Crystallization and Mechanical Properties

Abstract

In this work, 3D printed polylactic acid (PLA)/polycaprolactone (PCL) nanocomposites with favorable thermo-responsive cyclic shape memory effects (SMEs) and crystallization and mechanical properties were fabricated using a two-step method. First, an isocyanate-terminated PCL diol (PCL-NCO) was synthesized through the reaction between isocyanate groups of hexamethylene diisocyanate and active hydroxyl groups of PCL diol, and its physicochemical properties were characterized. A PLA/PCL blend with a PCL content of 50 wt% was fabricated via fused filament fabrication (FFF) 3D printing, and the influence of the PCL-NCO on the SME of the PLA/PCL blend was studied. The results indicated that the PCL-NCO significantly improved the cyclic shape memory performance of 3D printed PLA/PCL blends and was proved to be an effective interface compatibilizer for the blend system. Subsequently, the structure and properties of 3D printed PLA/PCL nanocomposites were investigated in detail by adding cellulose nanocrystal-organic montmorillonite (CNC-OMMT) hybrid nanofillers with different contents. It was found that the hybrid nanofillers greatly enhanced crystallization and mechanical properties of the nanocomposites due to adequate dispersion. The modification of the PLA/PCL blend and the preparation of the 3D printed nanocomposite can not only prolong the service life of a shape memory polymer product, but also broaden its application scope in advanced fields.

Recent Advances in Polymer Nanocomposites: Unveiling the Frontier of Shape Memory and Self-Healing Properties—A Comprehensive Review

“…Three-dimensional-printed PLA/PCL-based TRSMPs with cellulose nanocrystal-organic montmorillonite (CNC-OMMT) provide a versatile shape recovery ability of 99% at 65 • C. Increasing the nanofiller constituent reduces the recovery ability due to hindrance in chain mobility. The nanofiller increased the flexural strength, tensile strength, and notched impact strength by 37.1%, 25.8%, and 24.2%, respectively [113].…”

“…Increasing the nanofiller constituent reduces the recovery ability due to hindrance in chain mobility. The nanofiller increased the flexural strength, tensile strength, and notched impact strength by 37.1%, 25.8%, and 24.2%, respectively [ 113 ].…”

Cellulose-Reinforced Polylactic Acid Composites for Three-Dimensional Printing Using Polyethylene Glycol as an Additive: A Comprehensive Review

“…However, within this set of works, nine manuscripts diverge from the focus on PLA/cellulose composites. Instead, they explore blends (such as PLA/PCL) [119], the utilization of cellulose derivatives (like hydroxypropyl-methylcellulose) [120], or the integration of hemicellulose (such as galactoglucomannan (GGM)) as a filler for PLA [121]. Most published studies regarding cellulose-reinforced PLA composites center around the use of natural reinforcement at the nanometer scale.…”

Theoretical and Experimental Investigation of 3D-Printed Polylactide Laminate Composites’ Mechanical Properties

“…All materials displayed superior mechanical properties to those of human trabecular bone, even after undergoing degradation, with a mass loss of approximately 30% for polymer blends and 60% for composites. Liu et al [13] fabricated nanocomposites of PLA/PCL that exhibit favorable thermo-responsive cyclic shape memory effects as well as favorable crystallization and mechanical properties for 3D printing. Zhang et al [14] investigated the degradation behavior and mechanical properties of cellulose nanofiber (CNF)/PLA composites.…”