One-step surface modification for irreversible bonding of various plastics with a poly(dimethylsiloxane) elastomer at room temperature

Abstract

Here, we introduce a simple and facile method for bonding poly(dimethylsiloxane) (PDMS) to various plastics irreversibly via a one-step chemical treatment at room temperature. This was mediated by poly[dimethylsiloxane-co-(3-aminopropyl)methylsiloxane] (amine-PDMS linker), a chemical composed of a PDMS backbone incorporating an amine side group. Room temperature anchoring of the linker was achieved via a reaction between the amine functionality of the linker and the carbon backbone of the plastics, thereby producing urethane bonds. This resulted in the PDMS functionality being exposed on the plastic surface, mimicking the surface properties of bulk PDMS. Following corona treatment of the PDMS-modified plastic and a sheet of PDMS, the two surfaces were placed in contact with each other and heated at 80 °C for 1 h. This resulted in permanent bonding between PDMS and the plastic. To examine the effectiveness of the amine-PDMS linker coating procedure, the surfaces were characterized by measuring water contact angles and by employing X-ray photoelectron spectroscopy (XPS). Polycarbonate (PC), poly(ethylene terephthalate) (PET), poly(vinylchloride) (PVC), and polyimide (PI) were bonded successfully to PDMS using this method, with bond strengths of PC, PET, and PVC with PDMS measured to be approximately 428.5 ± 17.9, 361.7 ± 31.2, and 430.0 ± 14.9 kPa, respectively. The bond strength of a PC-PC homogeneous assembly, also realized using the proposed method, was measured to be approximately 343.9 ± 7.4 kPa. Delamination tests revealed that the PC-PC assembly was able to withstand intense introduction of a liquid whose per-minute injection volume was approximately 278 times greater than the total internal volume of the microchannel fabricated in PC. This demonstrated the robustness of the seal formed using the proposed technique.

Imprint Molding of a Microfluidic Optical Cell on Thermoplastics with Reduced Surface Roughness for the Detection of Copper Ions

“…After coating with an undiluted amine-PDMS linker and washing with IPA and drying, the water contact angle increased to 95.3 ± 0.9 , as shown in Fig. 2(b), 31 whereas that of the pristine PDMS was approximately 102.9 ± 0.9 , as shown in Fig. 2(c).…”

“…1(h). When partially cured NOA 61 reacts with the amine functionality of the amine-PDMS linker, any unreacted vinyl and ester functionalities within the partially cured NOA 61 can react with the amine functionality of the amine-PDMS linker, resulting in the formation of a urethane linkage [-NH-(C=O)-], 30,31 as shown in Fig. 1(i).…”

“…Vinyl and amine functionalities are also known to form a chemical bond (-CH2-CH2-NH-). [31][32][33][34] The coating performance was further verified by conducting contact angle measurements and XPS analyses. Figure 2 shows the results of water contact angle measurements of partially cured NOA 61 ( Fig.…”

“…Here, we detected rhodamine B, which is supposed to have a UV-vis absorption peak at 550 nm, [36][37][38] using the microfluidic optical cell imprint-molded on PET. A simple chamber was formed on PET (length, 8 mm; width, 8 mm; depth, 0.5 mm) and bonded with a flat PET via thermal bonding at 60 C under 0.1 MPa for 20 min, assisted by the amine-PDMS linker, 31 which was also used as an anti-adhesion coating material in this study. After bonding, the assembly was pasted onto a solid sample holder, which had an empty hole through which light could pass ( Fig.…”

Miniaturized polymerase chain reaction device for rapid identification of genetically modified organisms

“…To facilitate the thermal bonding of two PC substrates without deformation or collapse of the microchannel, the PC surface was first hydrophilically modified. The hydrophilic modification of PC was easily realized by forming a urethane linkage employing amine-terminated chemicals because the amine functionality can react with the carbonate backbone of PC by aminolysis (Wu & Lee, 2014;Zhang, Trinh, Yoo, & Lee, 2014). Oxidation of the alkoxy terminals of the amine-terminated chemicals on both PC surfaces ensures bonding through the formation of robust siloxane bonds (SieOeSi) under relatively mild conditions such as atmospheric pressure and a temperature lower than the T g of PC.…”