Self Assembly Materials and Contact Printing Materials
Introduction
Self-assembly materials and contact printing materials play an important role in current research and life. Self-assembling materials are used in self-assembly technology, which are designed to create new functional materials. Contact printing materials are used in microcontact printing (μCP) technology and aim at rapid patterning of micro and nano structures. Since they are both chosen from nanomaterials, molecular materials, organics materials, etc., which share many commonalities and some differences.
Commonalities
Small molecules for self-assembly generally have a head structure attached to the substrate, and a highly ordered tail structure with different functional groups away from the substrate, which is also meeting the characteristics required for contact printing materials. The contact printing technology is developed on the basis of self-assembly technology. For example, for common mercaptan inks, mercaptan molecules can be covalently bound to gold. When the seal loaded with mercaptan "ink" contacts the substrate, a self-assembled monolayer can be created on the gold substrate with a chemical reaction occurs. The mercaptan molecule is not only a self-assembly material, but also a contact printing material. In addition, in nanomaterials, carbon nanotubes (CNTs) can be prepared by self-assembly technology, or a single wall carbon nanotube aqueous solution stabilized by a surfactant can be deposited on a seal as a contact printing material using a controlled flocculation process, and patterned CNT films can be prepared by transferring CNT ink to other substrates using μCP technology.
Differences
For self-assembly materials, since there is no transfer of materials in the whole process, it is not necessary to consider the adhesion of materials to the target substrate. However, for contact printing materials, adhesion needs to be considered. For the transmission of contact printing materials, the most critical point is that the binding ability between molecules and substrate is stronger than that of seals, that is, the chemical properties of seals and substrate surfaces determine the transmission efficiency of ink. For example, for the ink with certain viscosity, a small amount of glycerin can be added to enhance the physical adsorption of the ink on the substrate. By applying a certain pressure, the ink loaded on the seal can be transferred to the substrate surface.
Application
Self-assembled materials and contact printed materials that have high commonality have been used in a wide range of applications. Currently, the application of both in biomedical field has become a hot topic, such as in the field of DNA, or organic matter as a matrix, polymers or other complexes through self-assembly technology or contact printing technology with the matrix to form a laminated composite film, this bionic material's performance may be improved, and its application will be of great interest.
References
- Cheng, C. M., Mazzeo, A. D., Gong, J., Martinez, A. W., Phillips, S. T., Jain, N., & Whitesides, G. M. Millimeter-scale contact printing of aqueous solutions using a stamp made out of paper and tape. Lab on a Chip, 2010, 10: 3201-3205.
- Ikkala O, ten Brinke G. Functional materials based on self-assembly of polymeric supramolecules. science, 2002, 295: 2407-2409.