sensitive adhesive (psa resin type) has good low temperature resistance and high
temperature resistance. The condensable volatiles and mass loss rate are low,
and there is no characteristic of harmful gas escape. All kinds of pressure sensitive adhesive
tapes can be made to facilitate the sticking of the film. The monomers used in the polymerization can be divided into three categories:
It is an alkyl acrylate with a carbon number of 4-12 and has a viscous effect. The glass transition temperature of the polymer is from minus 20 ° C to minus 70 ° C. Commonly used are isooctyl acrylate and butyl acrylate.
These are some monomers with a higher glass transition temperature. It not only improves the cohesion of the glue, but also significantly improves the water resistance, bonding strength, transparency and the like.
This is mainly a monomer having a reactive functional group containing a double-needed monomer such as an acrylic acid derivative having a carboxyl group, a hydroxyl group, an amide group or the like. It can crosslink with other monomers, promote polymerization, speed up polymerization, and improve the stability of the glue.
The above three types of monomer polymers are thermoplastic resins, and the cohesive force is not ideal. In order to further improve the cohesive force and the bonding strength, a crosslinking agent capable of chemically reacting with the modifying monomer may be added. They are allowed to produce a crosslinked structure under heating, thereby greatly improving the performance of the glue.
Among the pressure sensitive adhesives used in the production of various pressure sensitive adhesive products, acrylic emulsion pressure sensitive adhesives account for about 50%. It can be seen that the acrylic emulsion pressure sensitive adhesive industry occupies a very important position. This is because it has the advantages of non-toxic, no waste pollution and no fire hazard, and low cost. In 1998, the output of BOPP acrylic pressure sensitive packaging tape reached 1.2 billion. There are many manufacturers, concentrated in Guangdong, Jiangsu and Zhejiang.
Acrylic pressure sensitive adhesive tape, double-sided tape, protective tape, masking tape, label tape and medical tape are not only in terms of output, but also have a great improvement in bonding and coating properties, and are suitable for various uses. Products are constantly emerging. Despite this, the acrylic pressure sensitive adhesive and tape industry is still dominated by a general-purpose type with a single variety. And it can not meet the needs of the market in terms of bonding properties, water resistance, heat resistance and moisture resistance. Some special tapes still need to be imported, such as high-strength double-sided tape, high-temperature masking tape, flame retardant tape, magic tape and solar film and marking tape.