All
| Term | Definition |
|---|---|
| Hopper Blender |
Mixes material such as virgin resin, regrind, blowing agents, fillers, and colorants in desired proportions. Materials to be blended are metered in ratio to a mixing chamber and then discharged into the hopper of the processing machine. |
| Hopper Loader |
A device for automatically feeding resins to hoppers of extruders, injection molding machines and the like. |
| Hot Runner Mold |
A mold in which the runners and secondary sprues are kept hot and fluid during the entire cycle and are not ejected in the molded part. This avoids the need for handling and reprocessing scrap normally generated from runners sprues. |
| Hydraulic Clamp |
Used in variety of molding and forming machines, a hydraulic clamp consists basically of a high speed, variable hydraulic pump, valving, a fast acting cylinder, and a high pressure cylinder. Cylinders can be single or combination units. The clamp closes the mold halves to form the part. |
| Hydrolysis |
Decomposition of a substance by reaction with water. |
| Hydrophilic |
Having a strong affinity for water. |
| Hydrophobic |
Lacking affinity for water. |
| Hygroscopic |
Readily absorbing and retaining environmental moisture. |
| IMAGin® |
MACtac's IMAGin is a wide-format high-performance digital media acrylic adhesive. It is designed for water, solvent, and UV based ink jet printing. Typical uses include wall graphics, vehicle wraps, floor graphics, tradeshow displays and signage. IMAGin is a registered trademark of the Bemis Company. |
| Immiscible |
Incapable of intermittently mixing, i.e. oil and water are immiscible. |
| Impact Strength |
Ability to withstand shock loading. |
| Injection Mold |
A mold used in the process of injection molding. The mold usually comprises two sections held together by a clamping device with sufficient strength to withstand the pressure of the molten plastic when injected, and is provided with channels for heating, cooling, and venting. |
| Injection Molding |
Injection molding is a repetitive process in which plastic is melted or plasticated, and injected into a mold. With thermoplastics the mold is kept at a temperature below the solidifying point of the plastic, causing the injected polymer to freeze, thus forming the article. After cooling, the mold opens and the article is ejected. |
| Injection Pressure |
Pressure applied to the injection ram to force the plastic from the barrel and into the mold (measured in psi or Mpa). |
| Inomer |
Thermoplastic that combines transparency with toughness, particularly at low temperatures. The polymer |
| Insert |
An article of metal or other material which is incorporated into a plastic molding either by pressing the insert into the finished molding or by placing the insert in the cavity so that it becomes an integral part of the molding. |
| Izod Impact |
A test for shock loading wherein a notched sample bar is held at one end and broken by striking. |
| Jetting |
Turbulence in the resin melt flow caused by undersized gate, an abrupt change in cavity volume, or low melt temperature. |
| Knife Coating |
An adjustable knife or blade controls. |
| Knockout Bar |
A bar which holds and actuates ejector pins(s) in mold. Used in ejection of molded piece from mold. |
| Knockout Pin |
A pin that ejects a molded piece the amount of coating material laid down on a moving from the mold web. |
| Laminar Flow |
The movement of one layer of fluid past or over another layer without the transfer of matter from one to the other. Laminar flow in injection molding is achieved by solidifying the layer in contact with the mold surface. This acts as an insulating tube through which material can flow to fill remainder of cavity. This process is essential to mold surface duplication. |
| Land |
1.The horizontal bearing surface of a semipositive or flash mold by which excess material escapes. 2. The bearing surface along the top of the flights of a screw in a screw extruder.3. The surface of an extrusion die parallel to the direction of melt flow. 4. The mating surfaces of any mold, adjacent to the cavity depressions, which prevent the escape of material. |
| Ld Ratio |
The ratio of the length (L) to diameter (D) of an extruder or injection molding machine. This ratio can be expressed based on barrel length or screw flighted length. |
| Lead Chrome Pigments |
A series of inorganic pigments including yellows, oranges, and greens, used in polyolefins and other plastics. |
| Lensing |
Is a term which refers to a film defect which causes undesirable elongated thin voids in an extruded film. Are sometimes referred to as windows or air pockets. |
| Lexan® |
Lexan is the brand name for highly durable polycarbonate resin thermoplastic sheet in thicknesses from 0.75 mm to 12 mm and resin in a wide range of grades. Lexan is a registered trademark of SABIC Innovative Plastics (formerly GE Plastics). |
| Linear Low-Density Polyethylene |
See Linear Polymer. Includes polyethylenes ranging in density from 0.95 to 0.935. |
| Linear Polymer |
A polymer in which the monomeric units are linked together in linear fashion with little or no long chain branching. Examples are linear low-density polyethylene and high-density polyethylene. |
| Locating Ring |
Device which aligns nozzle of injection molding machine with the sprue bushing and the mold with the stationary platen. |
| Low-Density Polyethylene |
This term is generally considered to include polyethylenes ranging in density from about 0.915 to 0.925. In low density polyethylenes, the ethylene monomeric units are linked in random fashion, with the main chains having long and short side branches. This branching prevents the formation of a closely knit patter, resulting in material that is relatively soft, flexible and tough, and which will withstand moderate heat. |
| Lubricant |
A substance which when interposed between parts or particles tends to make surfaces slippery, reduce friction, and prevent sticking between the lubricated surfaces. Lubricants are added to plastics to assist flow in extrusion, assist in knitting and wetting of the resin in mixing and milling operations, and impart lubricity to finished products. |
| Lucite® |
Lucite is a cast acrylic sheet with a unique combination of high molecular weight and uniform thickness. Lucite is lightweight - half the weight of glass and 43% the weight of aluminum - and easily fabricated. It offers good weather resistance, rigidity, strength and stiffness and has greater safety than annealed glass. Lucite is a registered trademark of Lucite International. |
| Makrolife® |
Makrolife is a high-impact polycarbonate with UV protection. It is used for outdoor applications where glass is used today, with a 50% weight saving compared to glass. Makrolife has 10+ times the impact strength of high impact PMMA and more than twice the impact strength of PETG, yet is very easy to thermoform or cold bend into complex shapes. Makrolife is a registered trademark of Arla Plast. |
| Makrolon® |
Makrolon is the trade name for a family of high-quality polycarbonate sheet produced by Sheffield Plastics. Makrolon polycarbonate sheet is crystal clear and stronger than glass or acrylic sheet. Makrolon can be cut or cold-formed without preforming or fabrication. It is lightweight, durable and energy efficient. Makrolon is a registered trademark of Sheffield Plastics Inc. |