McAlindon(1) Former Senior Vice President, President of Designed Structures and Solutions (1) Ms. 1) Mr. The agreement provides that if (1) Mr.

ECert - 2023-11-22T151036.517.pdf Page 1 of 10 Validity of this certificate is based on the successful completion of the periodic surveillance audits of the management system defined by the above scope and is contingent upon prompt,written notification to ABS Quality Evaluations, Inc. of significant changes to the management system or components thereof. All rights reserved. 65537Certificate No: Facility: Avient Corporation - Cota, Colombia Autopista Medellín Km 2.5, Via Parcelas Km 1 Vereda Siberia Cota, Cundinamarca 250017 Colombia Facility: Avient Corporation - Gebze, Turkey Ihsan Dede Cad. Mariana Langiewicza 50 Lódzkie Konstantynow 95-050 Poland Activity: Design & Manufacture of Color, Additive Concentrate & Specialty Compounds Activity: Design and Manufacture of Colour and Additive Concentrates, Thermoplastic Resins and Specialty Compounds Facility: Avient Pakistan (Private) Limited 1-A/1, Sector-20 Korangi Industrial Area Korangi, Sindh 74900 Pakistan Facility: Avient Corporation - Lahnstein, Germany Hohenrhein 1 56112 Lahnstein, Rheinland-Pfalz Germany Activity: Design and Manufacture of Colour and Additive Concentrates, Thermoplastic Resins and Specialty Compounds Activity: Design and Manufacture of colour and additive concentrates, thermoplastic resins and specialty compounds Facility: Avient Corporation - Esenyurt, Turkey Orhan Gazi Mahallesi 1683 Sokak No:6 34538 Esenyurt Istanbul Turkey Facility: Avient Corporation - Jurong, Singapore No. 8 Third Chin Bee Road Jurong Industrial Estate Jurong 618684 Singapore Activity: Design and Manufacture of Specialty Engineered Thermoplastics Activity: Design and Manufacture of Colorants and Additives for Plastics Page 5 of 10 ABS Quality Evaluations Avient Corporation ISO 14001:2015 Certificate Of Conformance ANNEX At Below Facilities: Validity of this certificate may be confirmed at www.abs-qe.com/cert_validation.

ECert - 2023-11-22T154408.223.pdf Page 1 of 10 Validity of this certificate is based on the successful completion of the periodic surveillance audits of the management system defined by the above scope and is contingent upon prompt,written notification to ABS Quality Evaluations, Inc. of significant changes to the management system or components thereof. All rights reserved. 65536Certificate No: Facility: Avient Corporation - Cota, Colombia Autopista Medellín Km 2.5, Via Parcelas Km 1 Vereda Siberia Cota, Cundinamarca 250017 Colombia Facility: Avient Corporation - Gebze, Turkey Ihsan Dede Cad. Mariana Langiewicza 50 Lódzkie Konstantynow 95-050 Poland Activity: Design & Manufacture of Color, Additive Concentrate & Specialty Compounds Activity: Design and Manufacture of Colour and Additive Concentrates, Thermoplastic Resins and Specialty Compounds Facility: Avient Pakistan (Private) Limited 1-A/1, Sector-20 Korangi Industrial Area Korangi, Sindh 74900 Pakistan Facility: Avient Corporation - Lahnstein, Germany Hohenrhein 1 56112 Lahnstein, Rheinland-Pfalz Germany Activity: Design and Manufacture of Colour and Additive Concentrates, Thermoplastic Resins and Specialty Compounds Activity: Design and Manufacture of colour and additive concentrates, thermoplastic resins and specialty compounds Facility: Avient Corporation - Esenyurt, Turkey Orhan Gazi Mahallesi 1683 Sokak No:6 34538 Esenyurt Istanbul Turkey Facility: Avient Corporation - Jurong, Singapore No. 8 Third Chin Bee Road Jurong Industrial Estate Jurong 618684 Singapore Activity: Design and Manufacture of Specialty Engineered Thermoplastics Activity: Design and Manufacture of Colorants and Additives for Plastics Page 5 of 10 ABS Quality Evaluations Avient Corporation RC14001®:2015 Certificate Of Conformance ANNEX At Below Facilities: Validity of this certificate may be confirmed at www.abs-qe.com/cert_validation.

ECert - 2024-03-22T110644.362.pdf Page 1 of 10 Validity of this certificate is based on the successful completion of the periodic surveillance audits of the management system defined by the above scope and is contingent upon prompt,written notification to ABS Quality Evaluations, Inc. of significant changes to the management system or components thereof. All rights reserved. 65537Certificate No: Facility: Avient Corporation - Cota, Colombia Autopista Medellín Km 2.5, Via Parcelas Km 1 Vereda Siberia Cota, Cundinamarca 250017 Colombia Facility: Avient Corporation - Gebze, Turkey Ihsan Dede Cad. Mariana Langiewicza 50 Lódzkie Konstantynow 95-050 Poland Activity: Design & Manufacture of Color, Additive Concentrate & Specialty Compounds Activity: Design and Manufacture of Colour and Additive Concentrates, Thermoplastic Resins and Specialty Compounds Facility: Avient Pakistan (Private) Limited 1-A/1, Sector-20 Korangi Industrial Area Korangi, Sindh 74900 Pakistan Facility: Avient Corporation - Lahnstein, Germany Hohenrhein 1 56112 Lahnstein, Rheinland-Pfalz Germany Activity: Design and Manufacture of Colour and Additive Concentrates, Thermoplastic Resins and Specialty Compounds Activity: Design and Manufacture of colour and additive concentrates, thermoplastic resins and specialty compounds Facility: Avient Corporation - Esenyurt, Turkey Orhan Gazi Mahallesi 1683 Sokak No:6 34538 Esenyurt Istanbul Turkey Facility: Avient Corporation - Jurong, Singapore No. 8 Third Chin Bee Road Jurong Industrial Estate Jurong 618684 Singapore Activity: Design and Manufacture of Specialty Engineered Thermoplastics Activity: Design and Manufacture of Colorants and Additives for Plastics Page 5 of 10 ABS Quality Evaluations Avient Corporation ISO 14001:2015 Certificate Of Conformance ANNEX At Below Facilities: Validity of this certificate may be confirmed at www.abs-qe.com/cert_validation.

Pro Forma Financial Information The Company acquired Avient Protective Materials (“Dyneema”) on September 1, 2022 (the “Acquisition Date”) and sold the Distribution segment on November 1, 2022. To provide comparable results, the company references “pro forma” financial metrics, which include the business results of Avient Protective Materials for periods prior to the Acquisition Date, as if the transaction occurred on January 1, 2021 and reflect Distribution as a discontinued operation. Three Months Ended December 31, 2023 2022 Reconciliation to Condensed Consolidated Statements of Income $ EPS(1) $ EPS(1) Net income (loss) from continuing operations attributable to Avient shareholders $ 27.8 $ 0.30 $ (17.0) $ (0.19) Special items, after tax (Attachment 3) 5.4 0.06 38.3 0.42 Amortization expense, after-tax 15.0 0.16 14.6 0.16 Adjusted net income / EPS $ 48.2 $ 0.52 $ 35.9 $ 0.39 (1) Per share amounts may not recalculate from figures presented herein due to rounding Year Ended December 31, 2023 2022 Reconciliation to Condensed Consolidated Statements of Income $ EPS(1) $ EPS(1) Net income from continuing operations attributable to Avient shareholders $ 75.8 $ 0.83 $ 82.8 $ 0.90 Special items, after tax (Attachment 3) 79.3 0.86 116.2 1.26 Amortization expense, after-tax 61.5 0.67 49.0 0.53 Adjusted net income / EPS $ 216.6 $ 2.36 $ 248.0 $ 2.69 (1) Per share amounts may not recalculate from figures presented herein due to rounding 1 Three Months Ended December 31, Year Ended December 31, Reconciliation to EBITDA and Pro Forma Adjusted EBITDA 2023 2022 2023 2022 Sales - GAAP $ 719.0 $ 790.4 $ 3,142.8 $ 3,396.9 Pro forma APM adjustments — — — 256.1 Pro forma adjusted sales $ 719.0 $ 790.4 $ 3,142.8 $ 3,653.0 Net income (loss) from continuing operations – GAAP $ 27.6 $ (16.6) $ 76.3 $ 83.1 Income tax (benefit) expense (7.0) (60.8) 11.0 (19.3) Interest expense 26.8 49.4 115.3 119.8 Depreciation and amortization from continuing operations 44.2 48.6 188.8 162.5 EBITDA from continuing operations $ 91.6 $ 20.6 $ 391.4 $ 346.1 Special items, before tax 22.4 104.3 114.6 194.0 Interest expense included in special items (0.1) (16.0) (2.3) (26.0) Depreciation and amortization included in special items — (1.5) (1.9) (5.5) Adjusted EBITDA $ 113.9 $ 107.4 $ 501.8 $ 508.6 APM pro forma adjustments - 8 months 2022* — — — 83.1 Pro forma adjusted EBITDA $ 113.9 $ 107.4 $ 501.8 $ 591.7 Pro forma adjusted EBITDA as a percent of sales 15.8 % 13.6 % 16.0 % 16.2 % * Pro forma adjustment for January - August 2022 APM results (period before Avient ownership).

Pro Forma Financial Information The Company acquired Avient Protective Materials (“Dyneema”) on September 1, 2022 (the “Acquisition Date”) and sold the Distribution segment on November 1, 2022. To provide comparable results, the company references “pro forma” financial metrics, which include the business results of Avient Protective Materials for periods prior to the Acquisition Date, as if the transaction occurred on January 1, 2021 and reflect Distribution as a discontinued operation. Avient 2011 and 2018 valuations reflect trailing 12 months EBITDA at December 31 of the respective years. 38 EV / 2023E EBITDA Historic Multiple 6.5 8.3 9.6 13.2 13.0 12.8 11.3 8.6 17.9 16.8 10.7 8.8 8.8 8.7 7.5 6.9 A vi e n t (2 0 1 1 ) A vi e n t (2 0 1 8 ) A vi e n t (2 0 2 3 ) K W R P P G R P M A V Y F U L E C L H X L F M C S C L C E A S H E M N H U N Reconciliation of Non-GAAP Financial Measures (Unaudited) (Dollars in millions, except for per share data) Senior management uses comparisons of adjusted net income from continuing operations attributable to Avient shareholders and diluted adjusted earnings per share (EPS) from continuing operations attributable to Avient shareholders, excluding special items, to assess performance and facilitate comparability of results.

POLYMER FAMILY MATERIAL PRODUCT NAME DOSAGE Polyolefin PEA0820031 CESA Nox PEA0820031 0.5–1% Polypropylene PPA0820055 CESA Nox PPA0820055 0.5–1% Polyamide ABA0820029 CESA Nox ABA0820029 0.5–1% Polyester NBA0820022 CESA Nox NBA0820022 0.5–1% Polycarbonate NCA0820015 CESA Nox NCA0820015 0.5–2.5% Styrenic SLA0820009 CESA Nox SLA0820009 0.5–2.5% TPU RUA0820029 CESA Nox RUA0820029 0.3–1.5%

CESA™ Release Additives Lubrication PRODUCT SELECTION GUIDE CESA RELEASE – STANDARD OFFERINGS POLYMER FAMILY MATERIAL PRODUCT NAME DOSAGE Polyolefin PEA0820046 CESA Release PEA0820046 0.5–2.5% Polypropylene PPA0820053 CESA Release PPA0820053 0.5–2% Polyamide ABA0820031 CESA Release ABA0820031 1–3% Polyester NGA0820008 CESA Release NGA0820008 1–2% Polycarbonate NCA0820014 CESA Release NCA0820014 1–2% Styrenic SLA0820008 CESA Release SLA0820008 1–5% TPU RUA0820025 CESA Release 20025 0.5–2% CESA Release additives can be used in combination with other CESA masterbatches, and formulations can be customized for most applications.

In this case, a top tier-1 automotive molder was routinely running cycle times longer than originally quoted, as inconsistencies in CFA performance were creating processing issues and generating more scrap. THE SOLUTION The Avient technical team leveraged expertise in liquid formulations with the science of dispersion to develop Excelite™ IM, a CFA solution that targeted automotive injection molding applications and would help address the issues of this tier-1 molder. This tier-1 molder could now achieve a uniform, statistical distribution of active CFA content with an added degree of control that is unrivaled in the industry today.

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. MAR2005)1, J2412, J2527; BO 116-01 Xenon Arc Weathering (Exposure Testing) SAE J361 Visual Inspection of Automotive Trim GM9302P, GMW17141 Stress Mark Susceptibility GMW14688 Scratch and Mar Resistance (Erichsen) BN108-13, BO162-01 Resistance to Scratching GMW3205 Resistance to Odor Propagation of Interior Materials 1 This laboratory’s scope contains a superseded method.