Recommendations

Frequently Asked Questions:

1. What is UHMW-PE?

UHMW Polyethylene is a Linear Polymer with a molecular weight in the range of 3,100,000 to 6,000,000. Therefore, UHMW-PE has a molecular weight average 10 times that of conventional high density polyethylene resin.

2. What are the benefits of UHMW-PE?

The high molecular weight is what gives UHMW-PE a unique combination of high impact strength, low co-efficient of friction and abrasion resistance that outwears carbon steel 10 to 1 making it more suitable for many applications where lower molecular weight grades fail.

3. Where is UHMW used?

UHMW is a self-lubricating material which exhibits excellent wear and abrasion properties in addition to extremely high impact strength. Markets which would utilize these attributes would be snowboard bottoms, material handling, packaging, food processing and automotive just to name a few. (More Info. See Applications Library)

4. What are my installation options for UHMW?

Crown Plastics Company offers two methods of adhering – the use of pressure sensitive systems (peel and stick) and “Treated For Bonding” allowing UHMW-PE to be bonded using epoxy systems or contact cements. The traditional method of mechanical fastening can also be used if preferred.

5. What is the temperature range of UHMW?

UHMW-PE can operate continuously up to 180 degrees F and intermittently at 220°F with custom formulations available to enhance the temperature range up to 300°F. UHMW-PE can perform without degradation at cryogenic temperatures (-452°F).

6. Is UHMW USDA and FDA approved?

Yes, UHMW-PE is FDA and USDA approved for use in food processing and medical applications.

7. Is UHMW UV stable?

In its natural state, UHMW-PE is not UV stable, but formulations are available to provide UV stability in natural, black or any custom color.

8. Is UHMW available in a conductive or anti-static form?

Crown Plastics Company can offer virtually all of their gauges in conductive or anti-static forms making it ideal for use in electronics or semi-conductor applications.

9. In what form is UHMW-PE available?

Crown Plastics can supply UHMW-PE from .003” through .125” thick in continuous coil from 1/4”up to 24” wide in roll form, cut to length pieces and in stamped parts.

10. What colors are available?

While natural (milky white) and black are standard stock colors, UHMW-PE can be produced in any color in the Pantone library. (More Info. See Products)

11. Are there any high performance blends that can be added to UHMW-PE?

Crown Plastics R & D department has done extensive research on numerous additives that can enhance a variety of properties of UHMW-PE thereby providing customized products to meet customer requirements. (More Info. See Products)

7 Steps To Selecting The Best Pressure-Sensitive Bonding & Fastening Tape

There are many things to consider when you are selecting a pressure-sensitive adhesive for an application.  While pressure-sensitive systems have significantly improved over the years, they have also become very specialized and may be susceptible to a variety of environmental conditions.  There are seven steps to follow to help ensure that the selection you have made is the correct one.

1. Determine The Continuous Operating Temperature

While rubber adhesive systems are very versatile and aggressive, this is one area that rubber systems do not do well.  Anything over 125F continuous will probably require an acrylic system.

2. Identify The Surface Energy Of The Substrate

It is the surface energy that determines whether a substrate is bondable or not.  Teflon and polyethylene have very low surface energies and are difficult to bond.  The surface of these materials will need some form of treatment to increase surface energy and enhance bondability.

3. Consider Whether The Adhesive Is Exposed To Concentrated Solvents

Some adhesive systems are very susceptible to solvent exposure and can break down the adhesive system.  Solvent exposure will require an adhesive with cross-linking to withstand exposure to these chemicals.

4. Determine If Adhesive Is Exposed To Weathering

Excessive moisture and temperature variations can also wreck havoc on a pressure-sensitive adhesive.  Knowing the varying temperature ranges will immediately determine if a rubber of acrylic is best suited.  The ability to repel moisture or function in a high moisture environment will also narrow down your adhesive selection.

5. Determine If Adhesive Is Exposed To Direct UV Exposure

Outdoor exposure and UV will break down a rubber based system rather quickly.  As a rule, acrylic adhesives are recommended for outdoor use.  They provide excellent UV stability and temperature performance.

6. Identify Any Migrating Agents Exposed To Adhesive

Some substrates may contain plasticizers or agents that may migrate to the surface.  These agents may interfere with the adhesives ability to latch on to the substrate and delamination may occur. In most cases a cross-linked acrylic will function well.

7. When In Doubt Give Us A Call

We know that it is difficult in many cases to be able to make a diagnosis on the spot.  Don’t hesitate to call our Customer Service Department at 800-368-0238.

The world of pressure-sensitive tape is very wide and diverse. It is critical that the proper adhesive is selected to reduce the possibility of failure.  If the seven step process is followed, the risk of failure is significantly reduced.

Recommendations For Applying UHMW Tapes

Proper surface preparation is the most critical element in the laminating operation. Products supplied with pressure sensitive tapes are subject to breakdown when in contact with contaminated surfaces.

A conscious effort on the part of the installer is required. The substrate should be as smooth and clean as possible. To prepare the substrate for bonding, wipe with a clean cloth. If oil or heavy contamination is present, you may need to use a totally evaporating solvent such as lacquer thinner or MEK. If only light soil and surface dust is present, an isopropyl wipe should be sufficient. Turn the cloth frequently to avoid decontaminating the surface.

When clean and dry apply the pressure sensitive system. Be careful when pulling off the release liner, refraining from contact with the adhesive as this could potentially reduce bond strength. It is recommended that when applying long lengths, only remove 24″ to 36″ of liner at a time to make it easier to control. Once the product has been installed, a “J” roller or hand roller should be used to assure proper pressure and secure the bond. It is recommended that the temperature be above 50 degrees Fahrenheit when applying pressure sensitive tapes.

Removing or Replacing UHMW Tapes

When removing UHMW tapes, pry up one corner with a screwdriver or scraper and peel the plastic strip up using a pliers or vice grip. Remove residual adhesive using a clean rag and solvent such as lacquer thinner or permissible solvent. Do not use mineral spirits as it is oil based and will leave a residual film.

If the adhesive used was an Avery 8345, the adhesive uses a .0005″ mylar carrier as a support. When removing the adhesive, you may need to scrape the residue to break through this carrier. The remaining adhesive can be removed by wiping with a rag and solvent. Make sure the surface is clean and dry before applying new UHMW.