Avient 2024 Annual Report—Form 10-K Pages 19-20   GRI 419: Socio Economic Compliance 419-1

No. 0962.01) 09/05/2023 Page 1 of 1 SCOPE OF ACCREDITATION TO ISO/IEC 17025:2017 AVIENT CORPORATION 80 North West Street Norwalk, OH 44857 Craig Polta Phone: 419 660 4278 MECHANICAL Valid To: September 30, 2025 Certificate Number: 0962.01 In recognition of the successful completion of the A2LA evaluation process, accreditation is granted to this laboratory to perform the following tests on plastics: Test Method(s) Test Name ASTM D256; ISO 180 Notched Izod ISO 179 (1eA) Determination of Charpy Impact ASTM D523 Gloss ASTM D618 (Method A) Conditioning of Test Specimens ASTM D792 (Method A) Specific Gravity ASTM D1238 (Method B) Melt Flow Rate ASTM D3012 Thermal Oxidative Stability ASTM D3641 Injection Molding Test Specimens FMVSS 302 Flammability ASTM E1331; SAE J1545 Spectrophotometric Color Difference SAE J1885 (Rev. Trace McInturff, Vice President, Accreditation Services For the Accreditation Council Certificate Number 0962.01 Valid to September 30, 2025

Unified Seat Shell for Off-Road Recreational Vehicle Off-Road Vehicle Cargo Rack Gravi-Tech™ Luxury Closure (Spanish)

KN-419.S001-7007 DP 8685-4-9001(IDivy) DP 8685-4-5001(IDyell)

Avient Q2 2025 Earnings - August 1, 2025 Avient Q1 2025 Earnings - May 6, 2025  PolyOne Corporation at Credit Suisse Boston Basics Materials Conference

Avient Q2 2025 Earnings - August 1, 2025 Avient Q1 2025 Earnings - May 6, 2025  PolyOne Corporation at Credit Suisse Boston Basic Materials Conference

PINSTRIPE GREY 19-0203TPG 030GN2066 BOSTON GREEN YELLOW CORRECTOR 4

Both parts are made of silica/glass or polymer 4. Binder • PET, Polyester, Kevlar yarns coated with Swellcoat (absorbs and blocks water) 2 3 4 5 7 6 8 9. Cable jacket/sheath– Made of PE or PVC 9 Fiber-Line Product PolyOne Materials F I B E R O P T I C A L G R O W T H D R I V E R S PolyOne Corporation 20 5G Networks  Enable lower latency, greater flexibility & efficiency  Installation of these networks are in the very early stages  Installation will start in urban hubs and will continue to expand into suburban and rural areas  By 2025, only 14% of the world will have 5G connections  Growth is expected over multi- year period 5G technology will be a leading growth driver in fiber optic cable for several years 10x Speed Increase & 8x More Antennae Required 5G vs. 4G PolyOne Corporation 21 Safety Technology Geography Service FinancialPeople Low EH&S risk profile New and complementary technologies Leverage our global footprint Strong customer relationships Foundational operating margins of 8-10% with ability to double Motivated team with a specialty culture I N V E S T - T O - G R O W M & A S T R A T E G Y PolyOne Corporation 22 Capture sourcing synergies Cross-sell & blend technology 8-10% operating margins I N V E S T - T O - G R O W M & A P L A Y B O O K Protect customers Retain employees Implement LSS to drive efficiency improvements Innovate with combined portfolio Safety First!

Feb 04, 2025

Feb 04, 2025