Polyurea systems in general show comparable chemical resistance residential or commercial properties as that of comparable created polyurethane/ polyurea crossbreeds and also polyurethanes. This schedules mainly to the fact that all have the polyether backbone in the elastomer. The urea
link located in the polyurea as well as the hybrid system is more resistant to hydrolysis
than the urethane link.
Polyurea systems do often tend to have better resistance to alkali, high pH, than the hybrids or polyurethane systems. Aromatic polyurea systems are subject to chemical oxidation.
There are some more recent technologies of polyurea systems that are showing significantly
greater chemical resistance relative to very acidic environments. Remember that
chemical resistance/ performance can be straight related to handling conditions of the
polyurea systems. Those that do not attain full mix as well as contain porosity will
have reduced chemical resistance performance than those processed at the optimum
problems. This would consist of appropriate handling temperature levels as well as stress as well as
the correct mix setup in the spray gun.
These more recent modern technologies of polyurea systems have different polymer foundations in the chain. These can be polyester, epoxy, silicone, polyBD or polysulfide or a mix
of proprietary adjustments to the polymer chain. The following Figure 13 shows the affect of various acids as well as solvent on the Coast Hardness of 3 polyurea systems as 1 week immersion direct exposure. The HXP ISO 12 is a brand-new isocyanate quasi-prepolymer based upon a PolyDB backbone. It is compared to two conventional isocyanate quasi-prepolymers using a traditional polyether foundation. Note that the same kind resin mix part was used for every. Additional enhancement to the chemical resistance has been kept in mind utilizing material blends
containing phenolic, polyBD or polysulfide alterations as kept in mind above.
Improved Chemical Resistance Researches
The Fragrant polyurea systems have great resistance to ultraviolet light from an overall
performance viewpoint. Even with the use of UV Stabilizers/ Antioxidants, they will
nonetheless come to be stained and also discolor in time when made use of in light colors for outside
Aliphatic polyurea systems have excellent resistance to degradation by ultraviolet light
and are made use of for a range of exterior as well as interior atmospheric services. By modifying the
fragrant based systems with addition of aliphatic isocyanates or chain extenders, some
color stability improvement might be noted. However, these still have aromatic specie in
the polymer backbone and also are not color steady.
Based on the selection of application and also efficiency benefits of the polyurea
elastomer innovation, many applications area can be targeted. This would certainly include
locations frequently offered by polyurethane, epoxy, and also polyester technologies in addition to
polyethylene and polypropylene sheet goods.
For lots of coating applications, the need to return the facility back into service shortly
after the application is full is extremely advantageous. Polymer systems based on
polyurethane, epoxy and polymers generally call for at least a 12-hour treatment period, and also in
some case 24-hour, prior to the layered location can be taken into solution. Due to the quick,
regular reactivity and treatment times of polyurea systems, coating applications can quickly
be gone back to solution in a 1- to 3-hour amount of time. This technology can even be applied
at -20 ° C ambient temperature as well as reach service treatment within 1 hr.
Another very important function of the polyurea modern technology is the 100% solids nature with
no unstable organic compounds (VOC’s). During and also after application, no vapors, fumes
or chemicals are launched when properly processed. This makes the polyurea innovation
attractive for confined area application as well as for use in food processing/handling
The largest use the polyurea spray innovation remains in concrete coating applications. This
arrays from secondary containment to floor covering to water proofing approaches. The fast
reactivity and also remedy of the polyurea spray innovation permits quick application and
minimum downtown for the facility where the coating is being used. For the
application job, the concrete surface area is abrasive blown up, cleaned and vacuumed
adhered to by application of a primer system.
The most famous concrete coating application is secondary containment. Right here the
polyurea system can be easily used around projection and sticks well to tank
grounds and pipes through the concrete. For extremely chemical immune application, a.
topcoating can be used. An example can be seen in Number 14.
Polyurea elastomer base coat with chemical resistant overcoat.
Figure 14: Secondary Containment Location.
Polyurea spray elastomer systems are likewise being proclaimed as a brand-new system for parking deck,.
traffic locations and also floor covering. The application method coincides as that for secondary.
containment other than that a slower system may be required. This will allow the.
intro of a non-skid type aggregate product for grip objectives. Types of.
aggregate frequently used would be metal slag and also quartz or sand. Furthermore, slow-moving cure.
polyurea plural component caulk/sealant systems are utilized for the development joints.
These are applied by means of 2-part caulk tubes or proportioning tools.
In addition to intro of aggregate into the spray, the non-skid look can be.
done by spray method. The quick sensitivity of the polyurea technology will certainly give a.
consistent stipple result to the surface area of the coating. This structure serves for normal.
foot website traffic type floor covering applications.
For either highly harsh atmospheres or a much more visual charm, the polyurea.
modern technology can be used as a base coat system and then top covered with an epoxy or.
aliphatic polyurethane system. The polyurea system has the versatility to absorb typical.
movements in the substratum that would usually break the extra rigid top coating system.
Concrete surface areas can also be coated for corrosion defense, not always secondary.
containment applications. This would certainly be locations where salt spray or roadway movie has had a.
destructive affect on the concrete causing spalling and wear and tear. Regular thermal.
expansion and also contraction has actually likewise played an essential duty in the failings of the concrete.
An additional significant use for the polyurea spray modern technology is in direct immersion application.
such as storage tank and fish pond cellular linings. Here, the performance of the polyurea elastomer system.
need to be optimum so regarding hold up to these settings. The biggest application location.
would certainly be the wastewater/ procedure water market. For concrete tankage, the surface is.
prepared in a fashion a lot comparable to that as in the secondary containment. Figure 15 is.
an instance of a concrete wastewater storage tank lining application.
Figure 15: Concrete container lining.
In an additional concrete storage tank lining application, polyurea systems have been found to show no.
adverse impact on aquatic marine life, as well as there are some ANSI/NSF -61 approved.
systems for safe and clean water application areas. The effectively formulated systems have no.
off-gassing. The polyurea is utilized as a result of the quick handling time of the system and the.
long lasting, flexible residential or commercial properties of the movie. This permits development and also tightening of the.
storage tanks during extreme temperature level variants and also filling as well as discharging without fracturing.
Polyurea systems likewise perform well as lining systems for non-aqueous settings. In.
the instance of steel tankage utilized for gas kind storage space application, a minimum 3-mil blast.
account is specified as well as a high solids epoxy primer is used to insure optimum.
efficiency. Rate of application and also having the ability to return the storage tank back into service.
was the major factor for making use of polyurea. The elastomer system additionally performs well in the.
While not a straight concrete coating storage tank lining application, applying the polyurea spray.
elastomer system to geotextile has actually been made use of in secondary containment applications as.
The geotextile fabric, both woven as well as nonwoven, offers a nice consistent surface area for application of the polyurea elastomer system.
The material additionally enhances the tear as well as puncture resistance of the system, Number 16.
Figure 16: Covered Geotextile Application, CANADA.
While these applications highlight one of the most significant application areas for the polyurea.
spray innovation, there are numerous other interesting usages. Exterior coating to steel pipeline.
for deterioration protection is an expanding location. The polyurea technology enables pipeline to be.
re-coated in field atmospheres without using expensive coating treatment equipment. It.
has actually been reported that a polyurea system has actually been approved for use on the Alaska.
pipeline for repair applications. There are likewise numerous in-house brand-new pipe-coating.
applications involving polyurea spray elastomer systems.