Rubber to Metal Bonding Agent 830 Equivalent To Chemlok 250

Applying 830

1. Chemical Cleaning

Chemical treatments are readily adapted to automated metal treatment and adhesive application lines. Chemical treatments are also used on metal parts that would be distorted by blast cleaning or where tight tolerances must be maintained. Phosphatizing is a commonly used chemical treatment for steel, while conversion coatings are commonly used for aluminum.

2. Mechanical Cleaning

Grit blasting is the most widely used method of mechanical cleaning. However machining, grinding or wire brushing can be used. Use steel grit to blast clean steel, cast iron and other ferrous metals. Use aluminum oxide, sand or other nonferrous grit to blast clean stainless steel, aluminum, brass, zinc and other nonferrous metals.

For further detailed information on surface preparation of specific substrates, refer to Polyton Adhesives application guide. Handle clean metal surfaces with clean gloves to avoid contamination with skin oils. Apply 830 adhesive to stainless steel, aluminum, brass and other nonferrous substrates within one-half hour after cleaning. For ferrous substrates such as steel, a long layover can be tolerated if no rust is formed.

Mixing – Thoroughly stir Rubber to Metal Bonding Agent 830 before use, and agitate sufficiently during use to keep dispersed solids uniformly suspended. If needed, proper dilution for the various application methods is best achieved by experience. Give careful attention to agitation since dilution will accelerate settling.

Applying – Apply Rubber to Metal Bonding Agent 830 by brush, dip, roll coat, spray or any other method that gives a uniform coating and avoids excessive runs and tears. When using Rubber to Metal Bonding Agent 830 as a one-coat adhesive, the dry fi lm thickness should be 17.8-30.5 micron (0.7-1.2 mil). When used as a covercoat over a primer, the dry fi lm thickness of 830 adhesive should be 15.2-20.3 micron (0.6-0.8 mil).

1. Brushing

Apply full strength. The best bonds will be achieved by a uniform and complete surface coverage.

2. Dipping

Dilute adhesive with 10-25% xylene or toluene, by volume, to a Zahn Cup #2 viscosity of 30-48 seconds. Proper withdrawal will help reduce the tears and drip edges.

3. Roll Coating

Apply full strength. For best results, apply uniformly to surfaces.

4. Spraying

Dilute 830 adhesive with 25-50% xylene or toluene, by volume, to a Zahn Cup #2 viscosity of 21-24 seconds. The adhesive must be wet when it reaches the metal part. If drying occurs in the air before reaching the metal, cobwebbing and poor adhesion will result.

For electrostatic applications, dilute adhesive to a Zahn Cup #2 viscosity of 30 seconds, using technical grade methyl ethyl ketone (MEK) in ratio of 4 parts adhesive to 1 part solvent.

Drying/Curing – Allow the applied adhesive to dry until visual examination of the fi lm has shown that all solvent has evaporated. This will take approximately 20-40 minutes at room temperature. Drying time can be shortened by either preheating the metal inserts or oven

drying after application. Metal parts may be preheated to a maximum of 65°C (150°F) prior to adhesive application. For coated parts, moderate drying temperatures should be used, but temperatures as high as 149°C(300°F) may be used for very short periods of time. Maximum air flow at minimum temperatures will give the best results.

Dried films of Rubber to Metal Bonding Agent 830 are non-tacky; therefore, coated parts can be piled into tote pans for subsequent processing. Wear clean gloves when handling coated parts and cover the tote pans to prevent contamination by dirt, dust, grease, oil, etc. If coated parts are properly protected, long layover times between adhesive application and bonding usually have no adverse effect on the bond. If humidity is high, layover time will be shortened. If 830 adhesive has been removed by chipping or abrasion during handling, these damaged areas can be recoated before bonding.

Rubber to Metal Bonding Agent 830 can be used to bond rubber by compression, transfer, injection or other molding procedures used to make bonded parts. Maximum adhesion is obtained when the rubber has completely cured. Ideal bonding conditions exist when both the adhesive and the rubber cure at the same time. To accomplish this, load the adhesive coated metal parts in the mold and quickly fill the cavity with rubber.

Dry films of 830 adhesive remain firm at molding temperatures. During transfer or injection molding operations, the adhesive shows minimal tendency to wipe or sweep.

While it is desirable to keep mold loading cycles to a minimum to prevent pre-cure of the adhesive and the rubber, Rubber to Metal Bonding Agent 830 will resist moderate prebaking times without affecting bond performance. Transfer or injection molds need properly designed runners and sprues, as well as adequate pressures. This prevents rubber pre-curing before the mold cavities are completely filled.

Cleanup – Use solvents such as xylene and MEK to remove adhesive before heat is applied. Once cured, removal by solvent is not possible.

Packing

3.5kg/drum; 18kg/drum