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ANALYSIS of ALTERNATIVES and SOCIO-ECONOMIC ASSESSMENT

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ANALYSIS of ALTERNATIVES and SOCIO-ECONOMIC ASSESSMENT ANALYSIS OF ALTERNATIVES and SOCIO-ECONOMIC ASSESSMENT Legal name of applicant(s): Maflon Spa Submitted by: Maflon Spa (jointly developed with Acton Technologies Ltd) Substance: bis(2-methoxyethyl) ether (diglyme): EC 203-924-4: CAS 111-96-6 Use title: Use of bis(2-methoxyethyl) ether (diglyme) as a carrier solvent in the formulation and use of sodium naphthalide etchant for fluoropolymer surface modification whilst preserving article structural integrity (in-house processes). Use number: 1 ANALYSIS OF ALTERNATIVES CONTENTS LIST OF ABBREVIATIONS ....................................................................................................................................... 5 DECLARATION .......................................................................................................................................................... 6 1. SUMMARY ............................................................................................................................................................ 7 2. ANALYSIS OF SUBSTANCE FUNCTION.......................................................................................................... 9 2.1. The requirement to modify the surface of fluoropolymers ............................................................................. 9 2.1.1 Fluoropolymers ................................................................................................................................... 9 2.1.2 Chemistry of surface modification ...................................................................................................... 11 2.1.3 Solvated Electrons in surface modification and the use of sodium metal ........................................... 12 2.1.4 Radical anions in surface modification and the use of sodium naphthalide ........................................ 12 2.1.5 The measurement of the extent of surface modification...................................................................... 13 2.1.5.1 Change in colour ..................................................................................................................... 14 2.1.5.2 Change in surface physical characteristics (surface roughness) .............................................. 14 2.1.5.3 Change in surface chemical composition ................................................................................ 14 2.1.5.4 Change in surface wettability behaviour ................................................................................. 15 2.1.5.5 Change in bonding strength after application of an adhesive .................................................. 18 2.1.5.5.1 Etching and successful surface adhesion .............................................................. 18 2.1.5.6 Industry Standards applied for fluoropolymer etching applications ........................................ 19 2.1.5.6.1 ASTM Standards .................................................................................................. 19 2.1.5.6.2 Specific Industry Standards .................................................................................. 19 2.2. Technical function of diglyme in the wet chemical treatment fluoropolymer surfaces .................................. 21 2.2.1 Chemical functionality ........................................................................................................................ 21 2.2.1.1 Solubility of sodium naphthalide complex .............................................................................. 21 2.2.1.2 Thermal Stability ..................................................................................................................... 22 2.2.1.3 Flash Point ............................................................................................................................... 22 2.2.2 Process functionality ........................................................................................................................... 22 2.2.2.1 Process Temperature ............................................................................................................... 22 2.2.2.2 Process Reaction Time ............................................................................................................ 23 2.2.2.3 Solvent Viscosity ..................................................................................................................... 23 2.2.2.4 Bond strength .......................................................................................................................... 23 2.2.2.5 Polymer range .......................................................................................................................... 24 2.2.2.6 Tribology of surface requiring etching .................................................................................... 24 2.2.2.7 Diglyme recovery and recycling .............................................................................................. 24 2.2.2.8 In-house versus contract etching services ................................................................................ 24 3. ANNUAL TONNAGE............................................................................................................................................ 25 4. IDENTIFICATION OF POSSIBLE ALTERNATIVES ......................................................................................... 26 4.1. List of possible alternatives ............................................................................................................................ 26 4.2. Description of efforts made to identify possible alternatives .......................................................................... 28 3.2.1 Research and development .................................................................................................................. 28 3.2.2 Data searches ....................................................................................................................................... 28 3.2.3 Consultations ....................................................................................................................................... 28 5. SUITABILITY AND AVAILABILITY OF POSSIBLE ALTERNATIVES ......................................................... 29 5.1. WET CHEMICAL TREATMENTS .............................................................................................................. 29 4.1.1 Sodium – Ammonia System ................................................................................................................ 29 5.1.1.1 Technical feasibility ................................................................................................................ 29 5.1.1.2 Economic feasibility ................................................................................................................ 31 Use number: 1 Maflon Spa 2 ANALYSIS OF ALTERNATIVES 5.1.1.3 Reduction of overall risk due to transition to the alternative ................................................... 31 5.1.1.4 Availability .............................................................................................................................. 31 5.1.1.5 Conclusion on suitability and availability for sodium–ammonia etching alternative .............. 32 5.1.2 Sodium – Naphthalene – Alternative Solvents .................................................................................... 32 5.1.2.1 Substance ID and properties .................................................................................................... 32 5.1.2.2 Technical feasibility ................................................................................................................ 35 5.1.2.2.1 Physico-chemical Properties................................................................................. 35 5.1.2.2.2 Toxicological Properties ....................................................................................... 36 5.1.2.2.3 Process performance ............................................................................................. 36 5.1.2.3 Economic feasibility ................................................................................................................ 41 5.1.2.4 Reduction of overall risk due to transition to an alternative solvent ....................................... 41 5.1.2.5 Availability .............................................................................................................................. 42 5.1.2.6 Conclusion on suitability and availability for Alternative Solvent .......................................... 43 5.1.3 Other reductive pre-treatments involving radical anions ..................................................................... 44 5.1.3.1 Substance ID and properties ................................................................................................................ 44 5.1.3.2 Technical feasibility ................................................................................................................ 44 5.1.3.3 Economic feasibility ................................................................................................................ 44 5.1.3.4 Reduction of overall risk due to transition to the alternative ................................................... 44 5.1.3.5 Availability .............................................................................................................................. 45 5.1.3.6 Conclusion on suitability and availability ..............................................................................
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