Headquartered in Avon Lake, Ohio, USA, with world-wide operations encompassing more than 120 facilities and employing approximately 8,700 associates, Avient (formerly PolyOne) Corporation is a premier provider of specialized sustainable material. Board-level committee Avient’s Board recently collectively reviewed its role, and the roles of the Avient Board Committees, in sustainability and ESG. Headquartered in Avon Lake, Ohio, USA, with world-wide operations encompassing more than 120 facilities and employing approximately 8,700 associates, Avient (formerly PolyOne) Corporation, is a premier provider of specialized sustainable material.

PROXY SUMMARY Avient Corporation 33587 Walker Road Avon Lake, Ohio 44012 PROXY STATEMENT 2023 | Annual Meeting of Shareholders 1 • Shareholders of Record: If your shares are registered directly in your name with our transfer agent, EQ Shareowner Services, you are considered the shareholder of record with respect to those shares. Requests for copies of such Annual Report on Form 10-K should be directed to: Avient Center, 33587 Walker Road, Avon Lake, Ohio 44012, Attention: Secretary. B-2 (h) “Company” means Avient Corporation, an Ohio corporation, and its successors.

Attending and Voting at the Annual Meeting PROXY SUMMARY Company Operating Performance Our Company Culture PROXY SUMMARY Impact of Our Performance on Named Executive Officer 2018 Compensation Annual Incentive Plan 2018 Annual Incentive Program Payouts Named Executive Officer 2018 Target Opportunity ($) Payout (%) Payout ($) Long-Term Incentive Program 2016 – 2018 Cash-Settled Performance Units Performance Measure: Adjusted EPS Performance Periods Weighting Target Result Payout % PROXY SUMMARY Our Director Nominees and Committee Membership Name Age Director Since Principal Position Notable Skills and Experiences Independent Committee Membership* (M=Member, C=Chair) AC CC N&GC EH&SC PROXY SUMMARY Name Age Director Since Principal Position Notable Skills and Experiences Independent Committee Membership* (M=Member, C=Chair) AC CC N&GC EH&SC Average Tenure Average Age Gender Diversity 5.25 59 30% Governance Highlights Director Independence Independent Lead Director PROXY SUMMARY Board Oversight of Risk Management Stock Ownership Requirements Board Practices PROXY STATEMENT POLYONE CORPORATION PolyOne Center 33587 Walker Road Avon Lake, Ohio 44012 PROXY STATEMENT Dated March 28, 2019 ELECTION OF BOARD OF DIRECTORS PROPOSAL 1 — ELECTION OF BOARD OF DIRECTORS Our Board recommends a vote FOR all the nominees listed below. Requests for copies of such Annual Report on Form 10-K or for information on how to obtain directions to be able to attend the Annual Meeting and vote in person should be directed to: PolyOne Center, 33587 Walker Road, Avon Lake, Ohio 44012, Attention: Secretary.

Microbial susceptibility of various polymers and evaluation of thermoplastic elastomers with antimicrobial additives R E S E A R CH AR T I C L E Microbial susceptibility of various polymers and evaluation of thermoplastic elastomers with antimicrobial additives Zachary Zander1 | Deirdre Newton2 | Heather Scaglione1 | Averie Reiber1 | Parminder Agarwal2 1Avient Corporation, Avon Lake, Ohio, USA 2Lonza LLC, Morristown, New Jersey, USA Correspondence Zachary Zander, Avient Corporation, 33587 Walker Road, Avon Lake, OH 44012, USA. TPE samples were prepared by injection molding of 5 � 600 (12.7 � 15.24 cm) plaques, 0.12500 (3.175 mm) thickness using a Milacron™ Roboshot™ S2000i (Milacron, Batavia, Ohio) with a polished mold surface. Avient Corp., Avon Lake, OH) containing ZPT (Lonza Group AG, Morristown, New Jersey) was formulated into select grades of Versaflex™ and OnFlex™ GLS™ TPEs.

Autoinjector Pen - Avient Application Study.mm (1) AUTO-INJECTOR APPLICATION STUDY M A T E R I A L T E C H N O L O G I E S + S E R V I C E S F O R N E X T G E N E R A T I O N D E S I G N S Avient Corporation 1 Avient Corporation 2 Innovating Design Medical innovations and plastics have gone hand-in-hand to make healthcare safer, cleaner, and more accessible for all. WHY AVIENT? Avient Corporation 12

Avient’s chief operating decision maker uses these financial measures to monitor and evaluate the ongoing performance of Avient and each business segment and to allocate resources. Each of such adjustments has not yet occurred, are out of Avient’s control and/or cannot be reasonably predicted. For the same reasons, Avient is unable to address the probable significance of the unavailable information.

Avient’s chief operating decision maker uses these financial measures to monitor and evaluate the ongoing performance of Avient and each business segment and to allocate resources. Each of such adjustments has not yet occurred, are out of Avient’s control and/or cannot be reasonably predicted. For the same reasons, Avient is unable to address the probable significance of the unavailable information.

Certificate Avient de México, S.A. de C.V. Certificate Of Conformance This is to certify that the Quality Management System of: Avient de México, S.A. de C.V. Avient Corporation Contract Review, Customer Services, Human Resources, Information Technologies, Supplier Management 33587 Walker Road Avon Lake OH 44012 United States TXRMTP Avient Corporation Product Design, Testing 80 North West Street Norwalk OH 44857 United States 626R43 Copyright as of the Effective Date, ABS Quality Evaluations, Inc.

TERMS AND CONDITIONS الشروط والأحكام These Terms and Conditions govern the sale of Products to another (“Buyer”) by Avient Corporation and its affiliates (“Seller”). With respect to the state of Ohio, this waiver applies to Section 35 Article II of the Ohio Constitution and Ohio Revised Code Sec. 4123.74. . The law of the State of Ohio shall apply to these Terms, without regard to conflict of law principles.

Ashish Khandpur, President and Chief Executive Officer of Avient Corporation. To access Avient’s news library online, please visit www.avient.com/news-events. About Avient Avient Corporation (NYSE: AVNT) provides specialized and sustainable materials solutions that transform customer challenges into opportunities, bringing new products to life for a better world.