Rohacell is a closed-cell rigid expanded foam plastic based on PMI (polymethacrylimide), which does not contain any CFCs. The natural colour of Rohacell is white.

Rohacell has excellent mechanical properties, high dimensional stability under heat, solvent resistance, and particularly a low coefficient of heat conductivity. The strength values and the moduli of elasticity and shear are presently not exceeded by any other foamed plastic of the same gross density.

Machining
Rohacell IG is machined by means of high-speed tools designed for wood or plastics, without the use of lubricants. Dust must be carefully removed by vacuum. Common planing machines used for wood can also be used to plane edges and surfaces.

Milling
Grooves, rebates and other profiles can be cut with a routing cutter. With due care the material can be cut to lap joint widths of 2.00mm. Parts matching the contours of a template can be done with a suitable milling cutter.

Cutting
Thin sheets are cut with a knife. Thicker sheets can be scored halfway through and then broken. A particularly clean fracture is obtained by breaking the sheet at the edge of a table or desk.

Sawing
Circular saws are used for cutting sheets to size. Band, compass and jigsaws can be used for complex shapes

Stamping
Parts can be stamped out of thin sheets (max. 10.00mm thick). The maximum sheet thickness depends on the Rohacell grade used.

Sanding
Sanding can shape the foam sheet, using a steel template fixed to the sheet. Sanding is either done with an abrasive belt or by hand. For large parts a board covered with abrasive paper is used, which is drawn across the template by hand.

Thermoforming
Rohacell becomes thermoelastic and can therefore be shaped at a temperature of 170-190C. The required forming temperature depends on the degree of shaping and the density. Care must always be taken to see that the hot air sweeps uniformly over both sides of the Rohacell and that no heat is allowed to accumulate. The forming temperature must be accurately controlled in order to prevent secondary foaming. Cracks may form when shaping is too fast or done at too low a temperature.

Embossing
Another possible method of shaping is cold and hot embossing. For cold embossing the required shapes and profiles are pressed into the material during which time foam is compressed beyond its maximum compression strength. For hot embossing a heated embossing tool at 160-180C is pressed in to the foam. A nearly closed surface forms during hot embossing therefore polyethylene or PVC films can be sealed directly to the surface without any adhesive.

Cold shaping
It is possible for sheets to be cold bent. For this purpose the foam plastic sheets are lined on one side with a thin, flexible skin (e.g. aluminium sheet) and bent in such a way that the skin absorbs the tensile forces. With this process the attainable bending radii is about twice the sheet thickness.

Painting
Rohacell can be painted or sprayed with most commercial paints (including nitro-cellulose lacquers). Emulsion paints of the kind used in the building trade are unsuitable because Rohacell does not resist alkaline media.

Bonding
All reaction adhesive systems are suitable for bonding Rohacell IG to itself or to other materials.