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How do I make the Alliance 2695 compatible with normal phase solvent, such as THF? - WKB4337

Article number: 4337


  • Alliance 2695


Review the Operator's Manual Appendix D for the recommended parts and solvents as referenced below:

  1. Degasser chamber: Part number 700011709 PERFORMANCEPLUS VACDEGAS CHAMBER STENTED
    • The standard degasser chamber internal fittings can shrink and swell over time with normal phase and GPC solvents.
    • Normal phase solvent will cause the internally sleeved plastic tubing to fall off and the chambers to fill with solvent and fail.
  2. Plunger seal recommendation: Review Appendix D  "GPC solvents and seal choices".
    • Part number WAT270938 for the SEAL, PLUNGER, PKG (2), 2690 (standard yellow seal, Fluoroloy G)
    • Part number 700001326 for the SEAL, CLEAR, 2 PACK, ALLIANCE (performance plus opaque seal, ultra high molecular weight polymer)
    • Note: Where other seals do not perform as expected in high organic composition, the use of black seals is another option:
      • Part number WAT271066 for the GFP Plunger Seal Kit (Optional Black)
  3. Seal wash recommendation: Review Appendix D "GPC solvents and seal choices".
    • The appropriate seal wash will extend the life of the plunger seals.
  4. Solvent miscibility: Review Appendix D  "solvent miscibility chart".
    • If the difference between the miscibility numbers of the two solvents is 15 or less, they are soluble.
    • Prime all solvent lines, purge the injection pathway, and make injections of the intermediate solvent.
    • Using immiscible solvents can cause problems with baseline and pressure stability.


  • MTBE can also be used with the 2695.  
    • The clear seals are probably the best for this solvent.
    • Use 100% MeOH for the seal wash with MTBE mobile phase.

2690, 2690D, 2690DUPGD, 2690UP, 2695, 2695D, 2695DE, 2695DEB, 2695DUP, 2695E, 2695EB, 2695INERT, 2695UP, A-10SSM, ALLCOLCLR, ALLCOLHTR, ALLCOLHTRB, eluent, EMPGPC, GPCV2K, methanol

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