Tailoring properties and processing of Sylgard 184: Curing time, adhesion, and water affinity

Abstract

The curing time, surface adhesion and water absorption characteristics of Sylgard 184 were modified through the addition of catalysts and fillers. Incorporation of small amounts of a platinum-based Karstedt catalyst greatly decreased curing time at room temperature, whereas the addition of talcum powder (talc), polytetrafluoroethylene (PTFE) and NaY zeolite fillers changed surface adhesion and functionality of Sylgard 184. Fourier-transform infrared spectroscopy (FT-IR), rheological and mechanical tests (tensile strength and hardness) were used to quantify the acceleration in the curing time. The surface adhesion was evaluated for aluminum and glass-like substrates using a 90° peel-off test. The interaction between fillers and Sylgard was studied by molecular dynamics simulations, which showed the interaction between NaY and Sylgard is This article is protected by copyright. All rights reserved. This is the author manuscript accepted for publication and has undergone full peer review but has not been through the copyediting, typesetting, pagination and proofreading process, which may lead to differences between this version and the Version of Record. Please cite this article as doi: 10.1002/app.48530 greater than that for PTFE. Water absorption studies indicated that 10 wt% NaY added to Sylgard 184 helped to improve water absorption, whereas incorporation of talc had the opposite effect.

Tuning Thermal and Mechanical Properties of Polydimethylsiloxane with Carbon Fibers

“…Hardness tests were run according to the methods noted by Murphy and coworkers [ 6 ]. Samples were kept in a dark environment at 25 ± 3 °C for the duration of the experiments.…”

“…Polydimethylsiloxanes (PDMSs), also called siloxanes or silicones, are widely used, silicon-based organic polymers that have backbone flexibility, low intermolecular interactions, low surface tension, biocompatibility, and thermal stability [ 1 , 2 , 3 ]. These properties make them appealing for many applications, such as textiles, coatings, construction, adhesive, electronics, photonics, transportation, and medical applications [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. However, PDMS has certain mechanical properties that limit its use in several applications.…”

Long-Term Thermal Aging of Modified Sylgard 184 Formulations

“…The hydrosilylation reaction entails Si–H groups interacting with vinyl moieties in the presence of a catalyst [ 10 , 11 , 12 ] to form new bonds between the two chemical groups. Once both parts A and B are mixed together, the polymer undergoes crosslinking and cures in 48 h with full mechanical properties being demonstrated after a week [ 13 ]. Although the standard mixing ratio of 10:1 resin to hardener produces a material that exhibits hyperelasticity, high surface adhesion, and low Young’s modulus, these properties can be altered for a variety of applications by increasing or decreasing the mixing ratio [ 13 , 14 ].…”

“…Once both parts A and B are mixed together, the polymer undergoes crosslinking and cures in 48 h with full mechanical properties being demonstrated after a week [ 13 ]. Although the standard mixing ratio of 10:1 resin to hardener produces a material that exhibits hyperelasticity, high surface adhesion, and low Young’s modulus, these properties can be altered for a variety of applications by increasing or decreasing the mixing ratio [ 13 , 14 ]. In addition to altering the mixing ratio, many complementary products exist for changing viscosity and curing times [ 15 ].…”

Facile Photo and Thermal Two‐Stage Curing for High‐Performance 3D Printing of Poly(Dimethylsiloxane)

“…Polydimethylsiloxane (PDMS) has been broadly used for prototyping devices, [ 1–3 ] stretchable electronics, [ 4–6 ] microfluidics, [ 7–9 ] and medical devices, [ 10 ] with the excellent biocompatibility, flexibility, transparent, and gas permeability. [ 11,12 ] Recently, three‐dimensional (3D) printing of PDMS is attracting extensive attention due to the capability of achieving structures with high complexity by combining 3D printing's merits of freeform design and fabrication and rapid prototyping. [ 13–16 ] Concerns toward 3D printing, on the basis of solidification mechanisms, [ 17,18 ] require the precursors exhibit the properties either the light responsiveness for curing with the printing techniques of digital light process (DLP) and stereolithography apparatus (SLA), or the moderate rheology (namely, the moderate elastic modulus) for extrusion with the techniques of inkjet printing and direct ink writing (DIW).…”