Mechanical isotropy and postcure shrinkage of polydimethylsiloxane printed with digital light processing

Abstract

<jats:sec> <jats:title content-type="abstract-subheading">Purpose</jats:title> <jats:p>This paper aims to investigate the printability of photocurable PDMS with digital light processing (DLP) in terms of dimensional accuracy, mechanical properties, isotropy and postcure shrinkage.</jats:p> </jats:sec> <jats:sec> <jats:title content-type="abstract-subheading">Design/methodology/approach</jats:title> <jats:p>The photocurable PDMS was made from methacrylated PDMS-macromer and 2,4,6-Trimethylbenzoyldi-Phenylphosphinate (TPO-L) photoinitiator. The PDMS was printed using different orientations, sizes and post-exposure conditions and then evaluated by tensile test and microscope to determine the printability.</jats:p> </jats:sec> <jats:sec> <jats:title content-type="abstract-subheading">Findings</jats:title> <jats:p>Printed parts show good accuracy and low shrinkage, but high directionality in modulus, ductility and strength. The dimensional error is less than 2% and the shrinkage rates are less than 0.52%. In contrast, the modulus varies between 0.87 and 0.96 MPa depending on print orientation, elongation varies from 34.7% to 66.4% and strength varies from 0.23 to 0.49 MPa.</jats:p> </jats:sec> <jats:sec> <jats:title content-type="abstract-subheading">Originality/value</jats:title> <jats:p>This study quantitatively characterizes the printability of photo curable PDMS with DLP, which has not been reported elsewhere. This paper also discusses the challenges of PDMS printing for future advancement.</jats:p> </jats:sec>

Study on Chemical Graft Structure Modification and Mechanical Properties of Photocured Polyimide

“…The results are shown in Figure 9 . The result shows that the thermal decomposition temperatures 50 − 54 of linear PI and fully aromatic PI are significantly different. Compared with linear PI, the thermal decomposition temperature of all-aromatic polyimide is linear PI, mainly because all-aromatic PI has more benzene rings and a stable structure, which requires a higher temperature to break its bond energy.…”

Three‐dimensional chemical reactors: in situ materials synthesis to advance vat photopolymerization

“…Multiple studies have investigated the impact of print direction on the mechanical properties of materials made using VP and reported that they typically vary by less than 16%, [183][184][185] and can even be considered negligible in some cases. 56,171,[185][186][187] Although Kim et al recently reported that methacrylated polydimethylsiloxane materials fabricated using DLP printing had mechanical properties that varied by a factor of 2 in certain directions, 188 these materials were not postcured after fabrication, which has been shown to be critical in reducing the degree of anisotropy. 185 On the other hand, materials fabricated via FDM and SLS routinely exhibit mechanical anisotropies of approximately 30%-50% 171,189,190 and 10%-25% 171,191,192 respectively.…”

Additive Manufacturing for Neurosurgery: Digital Light Processing of Individualized Patient-Specific Cerebral Aneurysms

“…During the last few years, many technological improvements have been made for both 3D printers and materials [ 45 , 46 ], allowing a significant reduction of the related costs [ 17 ] and enhancing the final quality of the 3D printed models [ 47 ]. However, 3D printing technology still presents some limitations if compared to the most advanced neuroimaging methods, i.e., CTA and DSA, since these are commonly available in most hospitals and image processing takes a few minutes.…”