Applications of Silica/Polymer Nanocomposites

Introducing SiO2 into the polymer, the prepared nanocomposite exhibits excellent mechanical properties, thermal properties, optics, and electricity

01 Paints and Coatings

The polymer has good film-forming properties, and the addition of SiO2 endows it with excellent thermal stability and mechanical properties.

The researchers sprayed hydrophobic SiO2 on the surface of a polyurethane (PU)-acrylate (PUA) film to prepare a superhydrophobic coating for roll-to-roll or roll-to-plate systems with a contact angle of 150° and high light transmittance, suitable for in continuous production

SiO2 has high thermal stability and can be used to prepare flame retardant composite materials

In the same way, the SiO2 loaded with corrosion inhibitor is used as the filler coating to adhere to the metal surface, which can shield the influence of corrosion factors caused by the external environment

02 Biomedicine

SiO2 is non-toxic to cells and has good biocompatibility.

Compared with other porous materials, the pore size of SiO2 can be adjusted and the operation is simple, which provides more space for the design of the carrier structure for sustained drug release

The researchers polymerized magnetized SiO2 with the polymer guanidine, and used a novel bilirubin-induced fluorescent protein UnaG functional modification to prepare a composite material.

General medical imaging is based on magnetic resonance imaging.

03 Environment

The contribution of SiO2 nanocomposites to the environment is mainly reflected in the adsorption of heavy metals

SiO2 composite membrane also plays an important role in the field of oil-water separation.

04 Packaging

SiO2/polymer nanocomposites can enhance the barrier properties of traditional packaging in the form of coatings, or use themselves as packaging materials, especially with outstanding performance in water vapor barrier, which is undoubtedly beneficial to food preservation
.
In order to improve the shortcomings of traditional wrapping paper that are sensitive to gas, moisture and steam, the prepared polystyrene (PS)/SiO2 was used to roughen the surface fibers of wrapping paper
.
The results show that the waterproof performance of the packaging paper is the best when the mass fraction of SiO2 is 4%, and the mechanical properties are improved and the moisture content is decreased
.
The ultra-thin hydrophobic coating is deposited on the fiber matrix, which blocks pores and pores on the one hand, and acts as a barrier on the surface to prevent the fibers from contacting water molecules, thus making the wrapping paper hydrophobic
.

Researchers developed an active packaging film with mesoporous SiO2 (MCM-41) as the encapsulation container for eugenol and introduced poly(3-hydroxybutyrate-co-3-hydroxyvalerate) by electrospinning ) (PHBV)
.
The results show that the heat resistance, mechanical strength and barrier properties of the film to limonene and water vapor are all improved, and it has long-term antibacterial properties
.
At this time, SiO2 is not only used as a filler to enhance the performance of the film, but also as a container to reduce the release of bacteriostatic agents in the film, prolong the shelf life and protect the safety of food
.

SiO2 itself is non-toxic and tasteless, which can make up for the deficiencies of environmental-friendly packaging in terms of physical and chemical properties and meet the requirements of sustainable development
.
The researchers prepared SiO2-doped degradable starch films by a sol-gel method, and the results showed that the mechanical properties, optical properties, and barrier properties of such inorganic-organic hybrid films were enhanced, although the methods used still need to be improved.
, but also showed the development potential of SiO2 in hard degradable packaging materials
.

Source: "Feng Chunni, Liu Liu, Hu Chi, et al.
Research progress of silica/polymer nanocomposites [J].
Packaging Engineering, 2021, 42(03): 78-86"