Anaheim, Calif. — LSR processing, materials and markets underwent thorough reviews during the second international conference on advances in liquid silicone rubber and related thermosetting polymers.
Amos Golovoy, organizing committee chairman, said 197 people attended LSR 2018. Golovoy is president of AG Research in Canton, Mich.
Here are notes from some of the 28 presentations at the LSR 2018 conference and details from the live demonstrations at the related technical center visit.
Mark Bonifacio described LSR as an amazing young technology in his keynote address.
“Silicone is in the early stages … on the 10-yard line,” said Bonifacio, president of Boston-based Bonifacio Consulting Services LLC.
Bonifacio said global LSR market sales were $1.5 billion in 2015 and are on target to reach $3.29 billion by 2025, according to a report from Grand View Research Inc. of San Francisco.
Bonifacio described the raw thermoset material — he called it “goop” — as high-purity two-part platinum-cured silicone. Others described the raw material as “sticky” or “paste.”
The markets in the Asia-Pacific region and for medical and health care applications “are the biggest growth areas” for LSR, Bonifacio said. Among the principle drivers, processors “use silicone when other materials don’t perform as well.”
Bonifacio said LSR contract processors face challenges when major customers merge. He cited the Abbott Laboratories acquisition of St. Jude Medical Inc. in January 2017 and the Medtronic Inc. acquisition of Covidien plc in January 2015.
During the fourth quarter of 2018, Shenzhen Square Silicone Co. Ltd. plans to complete a 6,000-metric-ton-per-year expansion project in Zhejiang province in eastern China.
“Square will be able to produce 12,000 metric tons per year” and expects to replace Dow Corning as China’s largest LSR supplier, said YanMin Lee, chairman and founder of the Shenzhen-based Square.
“China’s increasingly stringent environmental policies have put pressure on siloxane producers,” Lee said. “The facilities are relatively backward, resulting in equipment maintenance rates becoming significantly higher than international rates. The increase of environmental protection policies has also increased production costs.”
Jacob Steinbrecher, applications engineer in electronics and lighting with Dow Corning, differentiated the recently rebranded DowSil moldable optical silicones from traditional LSR materials.
“Silicone resins impart strength and stability” in moldable optical silicones, he said. In comparison, “silica and/or other fillers impart strength and stability in traditional LSR.”
Steinbrecher said the DowSil products are “optically transparent, highly reflective [and] translucent.”
Particular applications include diffusers, protective covers, total-indicator-runout, Fresnel and free-form lenses; engineered diffusers, light guides, white reflectors and mixing chambers.
Experimental silica gains
Victor Lifton said Evonik Corp.’s newly developed EXP 107-2 experimental hydrophobic precipitated silica “shows unexpectedly positive influence on the behavior of the RTV-2 system at elevated temperatures.” Evonik of Piscataway, N.J., has ongoing tests of the LSR.
“Special grades of structure-modified fumed silica enable high loading levels without sacrifices in processability,” said Lifton, Evonik technical market manager.
Among the benefits: “low thickening effect and excellent processability at more than 20-percent loading levels, excellent reinforcement [and] no post-thickening effect,” Lifton noted. Moisture levels remain a concern and “optical properties are not as high as with fumed silica.”
Roembke emphasizes turnkey
Adam Shaal underscored the value of a turnkey system in leveraging design, build, test and support phases of a LSR project.
“We see more customers wanting to utilize turnkey systems for their production,” said Shaal, business development manager for Roembke Mfg. & Design Inc. of Ossian, Ind.
Roembke’s Asia-Pacific main office is located at the Hong Kong site of Everfinest Engineering Co. Ltd. In 2015, Everfinest cooperated with Roembke to introduce LSR tool, flashless and runnerless rubber mold and cold-runner valve-gate and open-gate systems to the Southeast Asia and China markets.
Hybrid mesh for simulation
Plastics simulation software provider Moldex3D says a new hybrid mesh — boundary layer meshing — is being used more frequently than the traditional voxel-type mesh for advanced LSR simulation technologies.
BLM validation with an end user confirmed the capability of the surface mesh to capture curvatures when necessary, said Jay Vang, customer success engineer with the Moldex3D North America Inc. unit in Farmington Hills, Mich.
The latest simulation technology for LSR molding leads to higher resolution, lower element count and faster simulation times, Vang said.
Users “need to capture precisely to measure viscosity differences,” said Torsten Kruse, president of Kruse Analysis Inc. in Naples, Fla., and a Moldex3D collaborator.
CoreTech System Co. Ltd. of Chupei, Taiwan, does business as Moldex3D.
Michael Kou successfully placed his iPhone in a container of water to demonstrate LSR’s capability to protect consumer electronics.
“The advent of LSR made ingress protection possible,” said Kou, U.S. market director for Singapore-based Synergy Hanil Precision Polymer Technologies Co. Ltd.
“Nothing is water proof, only water resistant,” Kou said. A fine-mesh ingress-protection design “allows air and sound to pass [and] keeps dust and water out” of a device’s audio jack, pressure vent, speaker, charging port, home button and microphone.
Future ingress-protection technologies such as ISO 20653-certified IPX9K will have the capability to withstand high-temperature water jets, outdoor and harsh environments and steam-autoclave sterilization applications.
Onward to high volume
Rick Ziebell discussed how fast LSR prototyping can allow speed-to-market responses and provide functionally-capable 3D printed parts.
Pairing Dow Performance Silicone’s new Evolv3D-brand technology and German RepRap GmbH printers can “provide ease of use and scalability to high-volume LSR injection molding,” said Ziebell, technology fellow with R.D. Abbott Co. Inc. of Cerritos, Calif.
GRR’s new liquid additive manufacturing printer frame enables the use of silicone and support material for more complex shapes, he said. The LAM is based on GRR’s X400 fused deposition modeling 3D printer.
The LAM printer’s improved software print control and expanded nozzle size option can yield finer print definition, Ziebell said.
R.D. Abbott, celebrating its 70th anniversary with roots in the rubber industry, has built an expertise in elastomers with premium products, testing laboratories and warehouses throughout the U.S. and Mexico.
ACH in Florida
ACH Solution USA Inc. has established an 800-square-foot sales office and 2,500-square-foot technical center in Sarasota, Fla., according to Steven Broadbent, general manager. The entity expects February delivery of a 120-ton Engel injection molding press with an integrated Viper linear robot.
The Florida operation is the newly formed U.S. unit of Christian Hefner’s Fischlham, Austria-based ACH Solution GmbH. The parent firm does more than 50 percent of its business in the U.S. and reported 2017 global sales of about 13 million euros ($15.6 million).
Broadbent was in technical sales positions with Engel Machinery Inc. of York, Pa., for 10 years before officially joining ACH on July 1.
In live demonstrations, LSR 2018 attendees saw production of eyeglass lenses, a radial seal and a medical specimen container during a tour at Engel Machinery Inc.’s west technology center in Corona, Calif.
A tie-barless 55-ton Engel Victory LSR machine with an integrated Engel Viper 6 robot produced the Wayfarer eye glasses using Shin-Etsu Silicones clear optical-grade x34-1972-3 on a one-cavity Roembke mold with 40-second cycles. 2KM North America Inc. supplied a SilcoStar e-flow 20 metering system.
An Engel 55-ton e-Mac LSR machine ran the radial seal using Momentive Performance Materials Inc.’s self-lubricating Silopren LSR 3286/50 on a four-cavity ACH mold with a 20-second cycles. Fluid automation specialist Graco Inc. supplied an F4 dosing system, and PolyOne Corp.’s GSDI Specialty Dispersions Inc. provided the colorant.
A Wintec 100-ton e-Win machine with a pick-and-place Engel viper linear robot ran the 13-gram polycarbonate in-development specimen container on a two-cavity Roembke mold on a 30-second cycles. Moretto USA Inc. supplied the feeder and dryer, and Lenzkes Clamping Tools Inc. provided the clamps. Engel designs and engineers the servo-electric high-precision Wintec product lines in Europe and manufactures the sister brand of Engel in Changzhou in China’s Jiangsu province.
More than 100 people attended the Engel open house.
Engel North America opened its 7,300-square-foot California technical center in 2009. Parent firm Engel Austria GmbH is based in Schwertberg, Austria.
LSR 2018 conference presentations took place Sept. 11-12 in Anaheim, and the Engel technical center event occurred Sept. 13 in Corona.