The Rubber Group Acquires Diversified Plastics, Inc.
Chattanooga, TN, March 24, 2026
River Associates Investments, L.P. (“River Associates”), a long-standing lower middle market private equity firm based in Chattanooga, Tennessee, is pleased to announce the acquisition of Diversified Plastics, Inc., (“DPI”) a precision plastics manufacturer, by its portfolio company, The Rubber Group (“TRG”), a 40-year leader in high-performance rubber solutions.
TRG and DPI bring complementary capabilities and shared values. The partnership strengthens the offerings of both companies, as rubber, plastics, and urethane capabilities are now accessible from an integrated, trusted source.
“The combination is about growth. We are bringing together complementary capabilities to better serve customers,” said Rob Pruyn, President, The Rubber Group. “By combining rubber, plastics, and urethane capabilities, we can offer a broader range of engineered solutions to both customer bases, and the cross-selling opportunity is significant.”
DPI will now be known as Diversified Plastics Industrial Solutions. It will continue to operate from its existing Missoula, Montana, facility with the same leadership team, workforce, manufacturing capabilities, and customer relationships in place.
“After 50 years of building Diversified Plastics, we were deliberate about what the next chapter would look like,” said Brad Reid, DPI. “Combining our expertise with The Rubber Group makes perfect sense, as it positions DPI to continue and even enhance our service to customers for another 50 years. We are aligned in how we treat our people, how we serve our customers, and how we collaborate.”
The companies serve overlapping industries, including water and wastewater, food and beverage, industrial manufacturing, and transportation.
TRG brings expertise in precision rubber sealing systems, custom-molded rubber components, and a full range of molding and fabrication processes, including overmolding, extrusion, transfer molding, and injection molding. DPI offers injection molded plastics, including proprietary UHMW-PE, thermoforming, CNC machining, urethane casting, in-house tooling and design engineering, and MultiFab Hybrid Component capabilities.
With facilities in New Hampshire, Chicago, and now Montana, the partnership expands TRG’s geographic footprint while providing DPI with access to a broader material platform, increased resources, and expanded commercial opportunity.
River Associates and the management team at The Rubber Group will continue to seek complementary strategic acquisition partners. For more information, please reach out to Mark Jones.
ABOUT THE RUBBER GROUP
Founded in 1986, The Rubber Group manufactures and distributes custom compression and injected molded rubber products, including grommets, bellows, bumpers, seals, and hoses. The Company’s products are often used in critical, high-cost-of-failure applications across a broad range of end markets, including medical, aerospace and defense, oil and gas, general industrial, and transportation. The Company is ISO 9001 certified, ITAR compliant, and FDA registered. More information is available at www.rubber-group.com.
ABOUT DIVERSIFIED PLASTICS INDUSTRIAL SOLUTIONS
Formerly known as Diversified Plastics, Inc., Diversified Plastics Industrial Solutions is a Missoula, Montana-based manufacturer of engineered plastic and cast urethane components serving the wastewater, lumber and forestry, food processing, mining, agriculture, grain handling, and industrial sectors. Celebrating its 50th anniversary this year, the company specializes in proprietary UHMW-PE injection molding and custom manufacturing solutions from concept through production. For more information, visit www.dpiplastics.com.
ABOUT RIVER ASSOCIATES
River Associates is a private equity firm based in Chattanooga, TN, which has focused exclusively on investing in the lower middle market for over 35 years. Target businesses can be privately held, private equity-backed, or divestitures from larger companies in the U.S. and Canada with initial EBITDA in the $3-12 million range. River Associates is opportunistic as to industry and has invested in numerous niche manufacturers, high margin distributors, industrial service providers and business service companies. Since its founding in 1989, River Associates has completed more than 125 transactions and is investing its eighth investment fund with $345 million of committed capital. For more information, visit www.riverassociates.com.