What is the different between extruded acrylic sheet and cast acrylic sheet?

What is the different between extruded acrylic sheet and cast acrylic sheet?

  It’s known that Acrylic Mirror is a finish product of acrylic sheet and there are 2 kind of acrylic sheet in the market, extruded acrylic sheet and cast acrylic sheet. Notice, whether formed by casting or extrusion, acrylic polymers are synthetic materials that result from a chemical reaction between a monomer and a catalyst.

  Let's talk about extruded acrylic sheet first. Extruded Acrylic sheets are manufactured by a continuous production process. Acrylic or PMMA pellets are fed from a containment silo to a feed hopper above an extruder line. The pellets are fed into the extrusion barrel and are driven through the barrel by a single or twin screw auger system.

  As the pellets progress through the heated zones of the extruder barrel the heat increases until the pellets melt into a molten mass.

 

  This molten mass is pushed forward into a conical / cone shaped die which then widens out into the die lips. The molten mass, under pressure from the screw drive, reaches the die lips and pushes outwards along the die lips to produce a molten sheet. The height / gap of the die lips is set slightly larger than the thickness required for the finished sheet. This continuous band of molten acrylic sheet is then passed through sets of cooling rollers, which may emboss a pattern / finish onto the sheet as it cools or may just produce a standard gloss / smooth finish.

 

  As the sheet progresses down the haul off line it has cooled sufficiently to be edge trimmed, cut to the final finished length required and a protective P/E film is applied. Finally, the sheets are palletized and wrapped for dispatch.

  Extruded sheets have a better tolerance on thickness, every thickness tolerance of acrylic mirror sheet of Goodsense is over or less 0.2mm. However, tighter tolerances can be achieved by prior agreement with the extrusion mill. Because of the continuous nature of production short production runs are of the order of 3 – 5 Tonne per size and gauge and colour. Clear, Opal and black are among the more standard colors produced.

  And how's cast acrylic sheet? Cast acrylic is a form of acrylic material that is produced by mixing the acrylic liquid ingredients in molds. Cast acrylic is a homogenous material that has equivalent properties in all directions. In the production process, the liquid ingredients are pumped into a mold made from glass plates. Then the mold is submerged in warm water. Here the polymerization process takes place. Cast acrylic sheets are hard to bend and shape. Cast acrylic materials are more resistant to scratches. Cast acrylic is hard to flame polish. The commercial name of cast acrylic is Perspex. Cast acrylic can be formed in various thicknesses.

  Casting is more labor intensive, making it more expensive. Casting yields a harder, sturdier, and more homogenous product. Casting lends greater chemical resistance over extrusion, making it the preferred material for uses involving fragrance, lotions, or other solvents. Available in a broad range of standard and custom colors for a variety of applications, cast acrylic is more pliable than extruded, less likely to bend, chip, or melt during milling. Because extruded material is limited in thickness, cast acrylic is a better option for larger structures, installations, etc.