Strictly-Extrusion

To combine the advantages of a conical extruder with the characteristics of a parallel twin-screw extruder Battenfeld Chen has introduced a new generation of conical screw design to the Chinese market, the active conical screw design. The special feature of this Battenfeld machine is its reduced flight depth in the feed zone and its increasing flight depth in the metering zone for a higher output rate per screw revolution. Therefore, it combines the benefits of the parallel process technology with the advantages of a conical gear concept. This system has also convinced customers, who use conical extruders for years and now replace their existing normal single conical machines. The new conical extruder is available as a main extruder and also co-extruder. More technical information (PDF file) contact : information@bce.battenfeld.com.cn

A new low-stress extrusion process for making film and sheet of very high optical quality is believed to be the first to use a free surface to form plastic film. The sheet is formed by flowing resin out of a long slot that runs along the top of the die. Resin then flows down two sides of the die and meets at the bottom, forming a low- stress film of molten plastic. The molten film is clamped and supported on both edges as it cools. Because the sheet of plastic isn’t formed between metal surfaces, the polymer chains aren’t oriented and the surface is very smooth.

The patented SFO (Stress-Free Optical) process is similar to that used to make optical glass. It is available for licensing from Rohm & Haas Co., Philadelphia. It targets plastic films and rigid substrates for LCDs, electroluminescent displays, optical windows and films, data-storage media, and other applications. Rohm & Haas has used the process to make developmental acrylic and PC films up to 20 in. wide and 1 mm thick.

Cenymer Corp. is establishing a facility for development and pilot production of diamondlike carbon film for solid-state devices. The firm recently relocated to a Longmont office park. In August, Cenymer obtained an exclusive worldwide license from the University of Massachusetts chemistry department to synthesize and purify a polymer precursor emanating from chloroform or bromoform monomers.

UK-based specialist compounder AEI Compounds is installing a new €2.2m twin screw compounding line at its facility at Gravesend in Kent. The investment, which includes an APV twin screw compounding extruder, will increase the firm’s speciality reactive compounding capacity from 12,000 to around 14,000 tonnes per annum, depending on product mix. The new line, which will be in production in the first quarter of this year, is the seventh at the site. According to AEI Compounds managing director Terry Brown, it is the first step in a planned two-year investment programme worth around €7.6m.

Southtech Plastics Inc. is investing more than US$1.5 million to add an extrusion line and enlarge its facility. In December, the maker of decorative sheet and roll plastic began installing a new Battenfeld-Gloucester 4½-inch coextrusion line. Commercial production is to begin in February. Southtech also added 2,000 square feet to house two 80,000-pound silos.

While the window market in France will register slight growth in 2003, the growth rates in the individual Departments will vary considerably. Growth in the new construction sector will waver between +97.1% and -69.7%, in the renovation sector between +13.4% and -10.1%, as a market report by consultants InterConnection (www.interconnectionresearch.com), Vienna, shows.

The new On-Line Laboratory ALFA from Optical Control Systems (OCS) incorporates a Film-Test-System which allows the measurements and recording of in-homogeneities and black specks as well as other physical, chemical and rheological parameters important in the production of polymers.The ALFA system combines a measuring extruder 20/25D (type 20/26) with gear drive, in combination with a Chill Roll (CR-7 or CR-8) and Winding Unit and is used in the production of narrow cast film especially for quality control during polymer production. This system is suitable for use in a laboratory or on-line. It is important that production is able to react quickly to any deviations from set values and so, the ALPHA system is usually installed close to the production process. With special rotating bypass systems, granules are directly taken from the process and
tested, with the excess granules being returned. The reaction of the system to deviations is usually determined by the length of time the material is in the extruder. With this system, response time is a maximum of three (3) minutes. During this time, the product is held in an intermediate silo. Aside from a purely optical assessment of film, the ALPHA also measures its thickness, as well as the concentration of any additives.