Certificate of Registration 9001:2015 MSP 9001:2015–MSP-ANAB-US (2.0) Page 1 of 2 Certificate of Registration of Quality Management System to ISO 9001:2015 The National Standards Authority of Ireland certifies that: Colorant Chromatics Ab Kroklundsvagen 346 AX-22 320 Odkarby Aland Finland has been assessed and deemed to comply with the requirements of the above standard in respect of the scope of operations given below: The Design, Manufacture and Sales of Fluoropolymer Color Concentrates and Compounds Additional sites covered under this multi-site certification are listed on the Annex (File No. 19.2540/C) Approved by: Geraldine LarkinChief Executive Officer Approved by: Lisa Greenleaf Operations Manager Registration Number: 19.2540/C Certification Granted: May 15, 1997 Effective Date: Oct 20, 2018 Expiry Date: Oct 19, 2021 National Standards Authority of Ireland, 20 Trafalgar Square, Nashua, New Hampshire, NH 03063, USA T +1 603 882 4412 9001:2015–MSP-ANAB-US (2.0) Page 2 of 2 Annex to Certificate Number: 19.2540/C Scope of Registration: The Design, Manufacture and Sales of Fluoropolymer Color Concentrates and Compounds Activity Location Central Management Group, Design, Manufacture Colorant Chromatics Kroklundsvagen 346 AX-22 320 Odkarby Aland Finland File No.: 19.2540/C Headquarters, Sales, Distribution Colorant Chromatics Europe B.V. Hastelweg 269 - 273 NL-5652 CV Eindhoven The Netherlands File No.: 19.2540/B Sales, Distribution Colorant GmbH Justus-Staudt-Strasse 1 Limburg-Offheim Germany 65555 File No.: 19.2540/A Design, Manufacture, Sales, Distribution Chromatics, Inc. 19 Francis J.

Date Of Certification: 11 December 2024 Date Of Expiration: 10 December 2027 IATF Certificate N°: 0558656 Bureau Veritas Certification Certificate No: FR094003 - IATF Revision: 1 For Bureau Veritas Certification Holding, Tour ALTO, 4 place des saisons, 92400 COURBEVOIE – France (The official document is in English. Any translations of this document shall be used for reference only.) 1/2 Certificate of Approval AWARDED TO PolyOne France Tossiat Route de la vavrette, 01250, Tossiat - France IATF USI: LWZS4P Bureau Veritas Certification certify that the Quality Management System of the above organisation has been audited and found to be in accordance with the requirements of IATF 16949 - FIRST EDITION and the applicable customer specific requirements SCOPE Design and manufacturing PERMITTED EXCLUSION(S) None PRODUCT(S) DELIVERED colour with additive concentrates for thermoplastic resins and speciality compounds obtained by mixing and extrusion https://e-cer.bureauveritas.com/68LJQE0ZV0CO6I7YW0YSXOUMV9WWROQPHPI2AOHRRLFFVRAVTFVZGXKWIE3TOWLTTKEWCPQB9UNAPXHH6T0HXOMUEDVYPRPJLEXBBTKQYPBRICYOKY143TECQ5UMHGA3JX Date Of Certification: 11 December 2024 Date Of Expiration: 10 December 2027 IATF Certificate N°: 0558656 Bureau Veritas Certification Certificate No: FR094003 - IATF Revision: 1 For Bureau Veritas Certification Holding, Tour ALTO, 4 place des saisons, 92400 COURBEVOIE – France (The official document is in English.

No. 0562.01) 11/30/2023 Page 1 of 1 SCOPE OF ACCREDITATION TO ISO/IEC 17025:2017 AVIENT CORPORATION 733 East Water Street North Baltimore, OH 45872 Claire Holman Phone: (419) 257-1327 MECHANICAL Valid To: October 31, 2025 Certificate Number: 0562.01 In recognition of the successful completion of the A2LA evaluation process, accreditation is granted to this laboratory to perform the following automotive plastics tests: Test Method: Test Name: ASTM D412 Tensile ASTM D523 Specular Gloss ASTM D618 (A) Conditioning of Plastics ASTM D624 (Die C) Tear Strength ASTM D638 Tensile Properties ASTM D792 (A) Density and Specific Gravity by Displacement ASTM D1004 Initial Tear Resistance ASTM D1203 (A) Volatile Loss ASTM D1895 (A) Apparent Density, Bulk Factor, Pourability ASTM D1921 Particle Size (Sieve Analysis) ASTM D2240 Durometer Hardness (Shore A and D) ASTM E1331 Color by Spectrophotometry Using Hemispherical Geometry FMVSS 571.302 Flammability FORD BN-102-01 (A) Low Temperature Flexibility FORD BO-131-03 Interior Odor ISO 3795 Determination of Burning Behavior of Interior Materials SAE J323 (A) Cold Cracking (Mandrel Bend) SAE J1351 Hot Odor for Insulation Materials SAE J1545 Instrumental Color Difference Measurement DOC-058151 Angle of Repose 1 Laboratory Developed Method For the tests to which this accreditation applies, please refer to the laboratory’s Mechanical Scope of Accreditation.

The round located at the base of a rib should be 25% of nominal wall thickness, and all ribs should have a draft angle from 1/4°– 1°. For t 1 = 1, K = 1. The typical width of this gate is 1–4 times the wall thickness.

Microsoft PowerPoint - 2021 Baird Sustainability Conference AVIENT CORPORATION (NYSE: AVNT) B A I R D S U S T A I N A B I L I T Y C O N F E R E N C E F E B R U A R Y 2 3 , 2 0 2 1 WALTER RIPPLE V I C E P R E S I D E N T , S U S T A I N A B I L T Y • 28 Years Industry Experience • Bachelors of Chemistry, Texas A&M University • Executive MBA, University of Michigan • Former VP & General Manager, Global GLS TPE Business • 2+ years Vice President, Sustainability Avient Corporation 2 SUSTAINABILITY A T A V I E N T P E O P LE P RO D U CT S P LA N E T P E R F O RM AN CE O U R M I S S I O N E N A B L E O U R C U S T O M E R S ’ I N N O V A T I O N A N D S U S T A I N A B I L I T Y G O A L S T H R O U G H W O R L D C L A S S P R O D U C T S A N D S E R V I C E S A N D E X C E L L E N C E I N T H E F O U R C O R N E R S T O N E S O F : Avient Corporation 3 Enable 100% of products manufactured for packaging applications to be recyclable or reusable. Reduce Scope 1 & 2 greenhouse gas emissions by 35%. Develop and implement solutions to end plastic waste while supporting AEPW $1.5B investment in key initiatives. 2030 SUSTAINABILITY TARGETS Avient Corporation 5 PRODUCTS 8 W A Y S W E H E L P C U S T O M E R S B E M O R E S U S T A I N A B L E TRENDS IN FOCUS Avient Corporation 6 RECYCLING / CIRCULAR ECONOMY LIGHTWEIGHTING ECO-CONSCIOUS SUSTAINABLE SOLUTIONS FOR THE CIRCULAR ECONOMY Avient Corporation 7 OPTICA™ TONERS FOR PET LACTRA™ SX LIGHT BLOCKING ADDITIVE FOR PET AMOSORB™ OXYGEN SCAVENGER FOR PET JOULE™ & SMARTHEAT™ INFRARED ABSORBER ULTIMATE™ UV LIGHT BARRIER CESA®-NATUR BIO-SOURCED ADDITIVES TRIPLE A™ ACETALDEHYDE SCAVENGER FOR PET IR SORTABLE BLACK FOR RECYCLABLE PACKAGING EZE™ SLIP AGENT FOR PET ONCOLOR™ NATURALS – COLORANTS FOR RECYCLABLE PACKAGING RESOUND™ OM THERMOPLASTIC ELASTOMERS VERSAFLEX™ POST- CONSUMER RECYCLED (PCR) TPE FORMULATIONS AVIENT CYCLEWORKS I N N O V A T I O N C E N T E R T O A D V A N C E T H E C I R C U L A R E C O N O M Y • Laboratory mimics real-world circular recycling in a research environment • Conducts chemistry testing to improve plastics recycling for customers • Screening and evaluation of additive and colorant systems during recycling • Collaboration platform for customers and value chain partners Avient Corporation 8 Avient Corporation 9 AVIENT ENABLES CUSTOMERS’ CIRCULAR ECONOMY GOALS C O L O R M A T R I X ™ P R O C E S S A I D & T O N E R F O R R E C Y C L E D P E T LIGHTWEIGHTING Avient Corporation 10 NYMAX™ NYLON FORMULATIONS HYDROCEROL® CHEMICAL FOAMING AGENTS POLYSTRAND™ TAPES AND LAMINATES COMPLĒT™ LFT ENGINEERED RESINS W H AT ’S H AP P E N IN G AV IE N T S O LU T IO N S PLASTICS ARE: AVIENT SOLUTIONS ENABLE LIGHTWEIGHT DASHBOARD SKINS H Y D R O C E R O L ® F O A M I N G A G E N T S O L U T I O N S Avient Corporation 11 ECO-CONSCIOUS Avient Corporation 12 ONCOLOR™ BRILLIANT METALLIC COLORANTS W H AT ’S H AP P E N IN G ONCOLOR™ WPC CAPSTOCK TECHNOLOGY ZODIAC™ AQUARIUS™ WATER BASED SCREEN PRINTING INKS MAGIQ™ FIBER COLORANTS & ADDITIVES SAFER & CLEANER MATERIALS RESOURCE CONSERVATION HUMAN HEALTH & SAFETY ECO-CONSCIOUS ALTERNATIVES AV I E N T S O LU T IO N S AVIENT ECO-CONSCIOUS SOLUTIONS IMPROVE FACE MASK PERFORMANCE Avient Corporation 13 M A G I Q ™ E L E C T R E T P L U S T E C H N O L O G Y Improved filtration efficiency Protects against aerosols & bacteria particles Increased shelf-life ENERGY INTENSITY 9% WASTE INTENSITY 2% WATER INTENSITY 20% TOTAL CO2 EMISSIONS 29% PLANET K E Y P E R F O R M A N C E I N D I C A T O R S 2 0 1 6 - 2 0 1 9 56 ENERGY REDUCTION PROJECTS SAVE 7400+ MT/CO2 ANNUALLY PUNE, INDIAASSESSE, BELGIUM Avient Corporation 14 • Avient is a founding member • Cross value chain collaboration • Driving breakthrough innovations REVENUE FROM SUSTAINABLE SOLUTIONS 2016 2017 2018 2019 2020PF VOC Reduction Reduced Energy Use Bio-derived Content Eco-conscious Renewable Energy Applications Recyclability Reduced Material Requirements Lightweighting $275M $325M $355M $410M $560M (1) Proforma to include a full year of Clariant Masterbatch business acquisitionAvient Corporation 16 Revenue from sustainable solutions expected grow at an 8-12% CAGR into the future (1) THANK YOU Avient Corporation 17

S ee S c if ic I s tr u c ti s o n ag e 3. 1 Name (as shown on your income tax return). The TIN provided must match the name given on line 1 to avoid backup withholding. Note: If the account is in more than one name, see the instructions for line 1.

The company noted that fourth quarter 2023 GAAP EPS includes $0.06 of special items (see Attachment 3) and $0.16 of intangible amortization expense (see Attachment 1). You are advised to consult any further disclosures we make on related subjects in our reports on Form 10-Q, 8-K and 10-K that we provide to the Securities and Exchange Commission. 5 Investor Relations Contact: Giuseppe (Joe) Di Salvo Vice President, Treasurer and Investor Relations Avient Corporation +1 440-930-1921 giuseppe.disalvo@avient.com Media Contact: Kyle G. NEWS RELEASE Attachment 1

Vents 1. Draft 1. Draft angle should be 1/2° to 1° per side.

Q2 2023 (TOTAL COMPANY) $824 $850 $131 $143 (in millions) $0.63 (in millions) Adjusted EBITDA Adjusted EPS 5 + 3% (+5% excluding FX) + 9% (+12% excluding FX) + 21% (+25% excluding FX) Sales 6 Q2 2024 RESULTS – ORGANIC SALES BY REGION VS PY 6 +5% +4% +1% +19% Avient ex. FX +4.6% FX -1.5% Total Avient +3.1% Note: Regional Sales Percentages exclude impact of foreign exchange Q2 2024 SEGMENT PERFORMANCE (COLOR, ADDITIVES & INKS) $525 $542 $94 $108 19.9% (in millions) (in millions) 7 17.9% +200 bps * Adjusted EBITDA Margin % • Organic sales growth in all regions led by Americas • Raw material deflation combined with cost reduction actions drove EBITDA margin expansion + 3% (+5% excluding FX) + 15% (+17% excluding FX) Q2 2024 SEGMENT PERFORMANCE (SPECIALTY ENGINEERED MATERIALS) $301 $308 $60 $64 20.6% (in millions) (in millions) 8 19.8% +80 bps * Adjusted EBITDA Margin % • Sales growth in consumer, healthcare and building & construction end markets offset by weaker demand in telecommunications • EBITDA margin expansion driven by positive end market mix as well as raw material deflation + 2% (+4% excluding FX) + 7% (+8% excluding FX) 2024 G U IDA N CE FY 2024 GUIDANCE Previous (May 7) Current Adjusted EBITDA $510 to $535 million $515 to $540 million Adjusted EPS $2.50 to $2.65 $2.55 to $2.70 Interest Expense $105 million $105 million Adjusted Effective Tax Rate 23% to 25% 23% to 25% Capital Expenditures ~$140 million ~$140 million 10 Q3 2024: Adjusted EPS of $0.62 11 Highlights • Provides performance updates on 2030 Sustainability Goals • Reduced company’s Scope 1 & 2 GHG emissions by 48% since 2019 • Highlights ESG performance ratings, certifications, and awards, including recent upgrades by Ecovadis to Gold and CDP to A- • Reflects Great Place to Work® culture focused on health, safety and employee engagement 2023 SUSTAINABILITY REPORT 11 Sustainability for a Better Tomorrow 2023 SUSTAINABILITY REPORT 12 • Investor Day to be held December 4, 2024 in New York, NY • The focus will be to do a deep dive on the Company’s strategy • Further details to be communicated 2024 AVIENT INVESTOR DAY AP P EN D IX 15 Performance Additives 15% Pigments TiO2 Dyestuffs Polyethylene 10%Nylon Polypropylene Styrenic Block Copolymer Other Raw Materials 38% ~40% hydrocarbon based (Grey shaded materials are hydrocarbon based, includes portion of “Other Raw Materials”) Non-hydrocarbon based materials RAW MATERIAL BASKET SEGMENT DATA U.S. & Canada 41% 36% 2023 SEGMENT, END MARKET AND GEOGRAPHY GEOGRAPHY REVENUESEGMENT FINANCIALS 19% 23%Industrial Building and 7% END MARKET REVENUE $2,007M $358M $1,138M $224M Sales EBITDA Specialty Engineered Materials Color Additives and Inks $502M$3,143M (1) 7% 17 (1) Total company sales and adjusted EBITDA of $3,143M and $502M, respectively, include intercompany sales eliminations and corporate costs 2023 REVENUE | $2 .0 B ILL ION 34% 37% 21% END MARKET REGION 18 34% 21% 15% Building & 1% Energy COLOR, ADDITIVES & INKS 2023 REVENUE | $1 .1 B ILL ION 52% 35% 19 6%Industrial 12% 10% Defense Building & END MARKET REGION SPECIALTY ENGINEERED MATERIALS 32% 26% Building & 6% 2% Defense 1% (18% of sales) 2023 AVIENT REGIONAL SALES 25% Building & (36% of sales)Transportation 22% Building & 12% 6% US & Canada (41% of sales) 59% 22% Building & LATAM (5% of sales) 20 BY END MARKET 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. A reconciliation of these measures to their most directly comparable GAAP measures is provided in the tables below. 2024 2023 Reconciliation to Condensed Consolidated Statements of Income $ EPS $ EPS Net income from continuing operations attributable to Avient shareholders $ 33.6 $ 0.36 $ 22.1 $ 0.24 Special items, after-tax 21.8 0.24 19.6 0.21 Amortization expense, after-tax 14.8 0.16 16.2 0.18 Adjusted net income / EPS $ 70.2 $ 0.76 $ 57.9 $ 0.63 Three Months Ended Reconciliation to EBITDA and Adjusted EBITDA: 2024 2023 Net income from continuing operations – GAAP $ 33.8 $ 22.3 Income tax expense 11.2 10.4 Interest expense, net 26.6 29.4 Depreciation & amortization 44.9 47.6 EBITDA from continuing operations $ 116.5 $ 109.7 Special items, before tax 28.1 21.7 Interest expense included in special items (1.0) — Depreciation & amortization included in special items (0.3) (0.1) Adjusted EBITDA $ 143.3 $ 131.3 Adjusted EBITDA as a percent of sales 16.9 % 15.9 % 1 2024 2023 Sales: Color, Additives and Inks $ 542.0 $ 524.5 Specialty Engineered Materials 308.1 300.8 Corporate (0.4) (0.9) Sales $ 849.7 $ 824.4 Operating income: Color, Additives and Inks $ 86.1 $ 68.0 Specialty Engineered Materials 42.8 39.7 Corporate (56.4) (45.4) Operating income $ 72.5 $ 62.3 Depreciation & amortization: Color, Additives and Inks $ 21.8 $ 25.7 Specialty Engineered Materials 20.8 19.9 Corporate 2.3 2.0 Depreciation & amortization $ 44.9 $ 47.6 Earnings before interest, taxes, depreciation and amortization (EBITDA): Color, Additives and Inks $ 107.9 $ 93.7 Specialty Engineered Materials 63.6 59.6 Corporate (54.1) (43.4) Other expense, net (0.9) (0.2) EBITDA from continuing operations 116.5 109.7 Special items, before tax 28.1 21.7 Interest expense included in special items (1.0) — Depreciation & amortization included in special items (0.3) (0.1) Adjusted EBITDA $ 143.3 $ 131.3 Adjusted EBITDA as a percent of sales: Color, Additives and Inks 19.9 % 17.9 % Specialty Engineered Materials 20.6 % 19.8 % 2 Year Ended December 31, 2023 Operating income: Color, Additives and Inks $ 259.9 Specialty Engineered Materials 142.5 Corporate (205.6) Operating income $ 196.8 Depreciation & amortization: Color, Additives and Inks $ 98.3 Specialty Engineered Materials 81.5 Corporate 9.0 Depreciation & amortization $ 188.8 Earnings before interest, taxes, depreciation and amortization (EBITDA): Color, Additives and Inks $ 358.2 Specialty Engineered Materials 224.0 Corporate (196.6) Other income, net 5.8 EBITDA from continuing operations 391.4 Special items, before tax 114.6 Interest expense included in special items (2.3) Depreciation & amortization included in special items (1.9) Adjusted EBITDA $ 501.8 3 Avient Q2 2024 Webcast Slides_for website_with non-GAAP_8_5.pdf IR Deck - AVNT-2024.06.30 - 8.02.24 1130AM.pdf Attachment Avient Q2 2024 Webcast Slides_for website_with non-GAAP.pdf AVNT cover slide.pdf

Sehyun Kim 1. REFERENCES 1. OM6258 tensile properties after 1 week at 70°C 2.9 2.1 3.2 2.1 3.5 Figure 9: Physical Property retention of OM 6258 after 1 week at 70°C.