PPS Thermoforming Thin-Walled Parts

Heated-housing can be thermoformed from PPS Thermoforming Plastics: Challenging Metals to Create High-Value Thin-Walled Parts

Thermoformed plastics are being called upon to take on more challenging and higher-value tasks in large, thin-walled parts, and thermoforming has begun to allow manufacturers to move away from metal in the manufacture of such parts and to avoid more expensive processing methods such as injection molding and machined profiles.

As thermoforming progressed in these more demanding applications, molders began to look for higher performance resins. Traditionally, they have used polymers from the lower tiers of the price/performance pyramid, such as Polypropylene, ABS, PVC, and hdpe. the search for high-performance thermoforming plastics has led to the adoption of polycarbonate, nylon 6, polyethersulfone, polyetherimide, PVDF, and now Polyphenylene Sulfide (PPS), which can be thermoformed.

Introduced in sheet and coil form in early 2004, PPS opens up new possibilities for aerospace, chemical, electronics, food and transportation applications PPS is a good alternative to fluoropolymers for chemical storage tanks because it is virtually inert to many compounds The development of PPS liners for large steel storage vessels is underway. the fiber backing on PPS can be bonded to the inner surface of the steel outer layer. The entire shell of small tanks can be thermoformed from PPS.

In prototype aircraft applications, PPS is thermoformed to form internal window frames. The molding allows the reveal to be larger and thinner than the corresponding injection-molded part, as the fusion lines formed in the molding are often a source of defects and scrap. Another aircraft application involves thermoforming 30% glass-filled PPS sheet to create overhead storage bins. The assembly measures 20 x 30 inches by 6 inches deep. The thermoformed control panel uses 15% glass-reinforced PPS to resist heat buildup inside the assembly unit. the 18 x 6-inch part is CNC-machined to cut windows and holes for a variety of equipment. Train and bus manufacturers are considering thermoformed PPS panels for walls and doors because they must withstand high temperatures and have low smoke generation. Thin-walled parts this large cannot be easily or economically manufactured through injection molding.

Thermoformed PPS is also used for oven trays that can withstand high temperatures for extended periods of time and replace aluminum and stainless steel. The 1.5-inch-deep PPS tray in development measures 20 x 30 inches and has rolled edges, which will replace stainless steel trays that must be periodically refurbished to remove burrs and baked-on food. It will replace stainless steel trays that must be periodically refurbished to remove burrs and baked-on food. pps trays do not require refinishing after use. pps was also selected for the 6-inch-deep thermoformed lighting cans and panels because of its ability to withstand the heat generated by high-intensity halogen lamps. 24 x 36-inch canisters are CNC-machined, and other applications evaluated include pressurized liners used in cleanroom exhausts and polished carriers used in the production of hard disk drives. polished carriers for hard disk drives.