The science behind it.

 

NSL8 is a highly flexible, thermally insulating, epoxy syntactic foam for

petrochemical, oilfield, marine, and industrial applications.

 

A flexible epoxy resin binder, NSL8 is used as flexible syntactic foam,

ballistic foam, bomb blast mitigation material, and waterproof

sealant and grout.

 

NSL8 is two-component epoxy syntactic foam supplied as a kit to be mixed at a 1:1 ratio by volume.  Once mixed, the material provides an adequate working time to allow it to be pumped, poured, or cast into a variety of configurations. Depending upon ambient temperature, the mixture should allow 30-45 minutes before starting to gel. The materials’ adhesion to clean surfaces is outstanding, providing a waterproof bond that virtually eliminates corrosion under the foam.  Once cured at ambient temperatures, the material is extremely tough yet flexible.  The high degree of flexibility prevents breakage and cracking usually associated with syntactic foams used in similar applications.

 

Features/Benefits

 

• Convenient 1:1 mix ratio by volume

• Long working time allows use in difficult configurations

• Minimal exothermic temperature rise during cure

• Ambient cure

• Outstanding bond strength to clean surfaces

• High flexibility prevents breakage and cracking

• Excellent thermal insulation properties

• Resistant to most chemicals and harsh environments

 

 

How to Use NSL8

 

NSL8 is supplied in two components, an epoxy resin and an amine curing agent.  Each component must be mixed by mechanical agitation separately prior to being combined with the other component.  Once mixed separately, the components are combined at a volume mix ration of 1:1 and mechanically agitated until a uniform mixture is achieved.  It is important that a uniform mixture is achieved to insure complete and full cure at ambient temperature. 

 

Once properly mixed, the material can be pumped or poured into place. The use of a plural component pump with heated hoppers and inline static mixer is highly desirable. In addition to insuring the proper mix ratio, plural component equipment will also minimize installation time, air entrapment, and material waste. Typical applications involve temporary molds around parts or equipment, or casting into spaces between permanently placed apparatus.  Adequate mold release agent must be applied to wetted surfaces of molds or parts that are to be removed, as the adhesion of NSL8 to a wide variety of surfaces is very tenacious.  

 

 

Surface Preparation

 

Surfaces to which NSL8 is to be adhered should be

clean, dry, and free from foreign matter.  For ultimate

adhesion, abrasive blasting is recommended. 

However, the adhesion to non-blasted surfaces is

excellent.  Although not optimum, NSL8 can usually

tolerate moderate amounts of surface contamination

consisting of particulate matter or small amounts of oil

or grease.  Continuous films of grease can sometimes

be useful as a mold release on surfaces to which

adhesion of the NSL8 is not desirable.

 

 

Forming

 

Forms or molds are to be liquid tight to prevent leakage prior to cure. The viscosity of mixed NSL8 is fluid enough to be poured into most forms or molds. Underwater placement must be done by pumping annulus from the bottom up or poured using a “tremie” method to eliminate material segregation from falling through water. Low exothermic temperature rise during cure permits substantial volumes to be poured all at once without molded shapes being distorted by differential temperatures.  Due to the high degree of flexibility of NSL8, most if not all, mechanical distortions due to mold design flaws or thermal differentials are eliminated.

 

Temperature

 

NSL8 is designed to be applied at normal ambient temperatures of about 70 deg. F.  Because the chemical reaction that occurs between the two components is temperature dependent, low temperatures will slow the reaction, and elevated temperatures will speed up the reaction.  Cure rate will slow substantially below 60 deg. F and effectively stop below 50 deg. F.  Handling time will be reduced by approximately half for every 15-20 degrees above 70 deg. F.

 

Curing

 

Cure time is temperature dependent.  At ambient temperatures of 70 deg. F, molds can usually be removed in 12 – 24 hours.  The time variance is due to the effects of mass, larger masses typically cure faster due to internally generated heat from the curing process, or exotherm.  Full cure at ambient temperatures of 70 deg. F will usually be achieved in approximately 7 to 10 days.  Substantial mechanical strength is obtained well before full cure so that parts or equipment may be moved without damaging the casting as soon as moderated cure is reached.

 

Cleanup

 

Flush plural component application equipment with fresh water followed by an epoxy clean-up solvent. Clean-up solvent can be reused multiple times, which minimizes waste disposal issues.