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    HomeProductsBasic & Fine ChemicalsChemical IntermediatesIsophthalic Acid CAS 121-91-5
    • Isophthalic Acid CAS 121-91-5
    • Isophthalic Acid CAS 121-91-5
    • Isophthalic Acid CAS 121-91-5

    Isophthalic Acid CAS 121-91-5

    Isophthalic Acid is supplied as an aromatic dicarboxylic acid intermediate, widely used in the production of unsaturated polyester resins, alkyd resins, and specialty polymers. It is valued for its ability to improve chemical resistance, thermal stability, and mechanical performance in resin systems.

    In commercial supply, this product is typically delivered as a white crystalline powder, suitable for polymerization and resin synthesis processes. It is used across coatings, composites, and engineering materials industries. Standard export packaging, batch documentation (COA, TDS, SDS), and supply support are available for both industrial production and bulk procurement.

    • CAS: 121-91-5
    • Synonyms: 1,3-Benzenedicarboxylic Acid; m-Phthalic Acid
    • Einecs: 204-506-4
    • Molecular Formula: C8H6O4
    • Grade: Industrial / polymer-grade supply
    • Package: Available in bags or bulk containers; packaging arranged according to order volume and handling requirements
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    Product Description

    1 Physicochemical Properties
    2 Typical Applications
    3 Packaging
    4 Storage
    5 FAQ

    Physicochemical Properties

    ItemDescription
    AppearanceWhite crystalline powder
    OdorOdorless or slight characteristic odor
    Melting PointApprox. 345°C (sublimes)
    Boiling PointDecomposes before boiling
    SolubilitySlightly soluble in water; soluble in organic solvents such as alcohols
    DensityApprox. 1.5 g/cm³
    Acidity (pKa)Approx. 3.5 / 4.5
    Thermal StabilityStable under normal processing conditions for polymer synthesis

    Typical Applications

    • Unsaturated polyester resins (UPR) for composites and fiberglass applications
    • Alkyd resins for coatings and paints
    • Engineering plastics and specialty polymers (e.g., PET modification)
    • Coating systems requiring improved durability and chemical resistance

    Application suitability should be evaluated based on processing requirements and regional regulatory considerations.

    Packaging

    Isophthalic Acid is supplied as a solid crystalline powder and packed in moisture-resistant bags or bulk containers suitable for industrial chemical handling. Typical packaging includes woven bags with inner liners or bulk bags for large-volume orders. Packaging is designed to prevent moisture uptake and contamination during storage and transportation, and can be arranged according to order quantity and logistics requirements.

    Storage

    Store in a cool, dry, and well-ventilated area. Keep containers tightly sealed to prevent moisture absorption and contamination. Avoid exposure to excessive humidity and direct sunlight. Maintain package integrity during storage and handling to ensure consistent product performance.

    FAQ

    • What type of chemical is Isophthalic Acid?
      It is an aromatic dicarboxylic acid used as a chemical intermediate in polymer and resin production.
    • What are the main application areas?
      It is widely used in polyester resins, alkyd coatings, and engineering plastics.
    • In what form is the product supplied?
      It is typically supplied as a white crystalline powder.
    • Is it suitable for polymer modification?
      Yes, it is commonly used to modify polymer properties such as chemical resistance and durability.
    • What documents are available with supply?
      COA, TDS, and SDS are typically provided.
    • Is bulk supply available?
      Yes, it can be supplied in bags or bulk packaging depending on order volume.

    FAQ - Technical & Supply Chain

    Documents

    Documents and Product Support

    For product review and sourcing evaluation, supporting documents can be coordinated according to the product type, inquiry stage, and order requirements.

    • COA for batch-based quality reference
    • TDS for key physical and chemical information
    • SDS / MSDS for handling, storage, and safety reference
    • Packing information for sample, trial, and bulk orders
    • Technical communication based on application and specification requirements
    Quotation

    Information to Confirm Before Quotation

    Clear sourcing information helps reduce specification mismatch and allows a more accurate quotation before sample or bulk order discussion.

    • Product name and CAS number
    • Application or intended end use
    • Required purity, grade, or specification
    • Sample quantity, trial order, or bulk demand
    • Preferred packing form or net weight
    • Destination country or port
    • Required documents or compliance expectations
    Storage & Handling

    Packaging, Storage, and Handling Notes

    Packaging form, storage conditions, shelf life, and shipment arrangements should be confirmed according to the product characteristics, package size, and destination requirements.

    Before order confirmation, buyers are advised to review the corresponding product documents and confirm whether any special storage, labeling, or handling requirements apply.

    Supply Support

    Sample, Bulk Order and Repeat Supply Support

    Support can be arranged for sample discussion, bulk supply planning, packaging confirmation, and routine sourcing communication based on the actual product and order requirements.

    For repeat-use formulations or long-term procurement plans, buyers may discuss specification consistency, packaging preferences, delivery expectations, and document coordination in advance.

    Contact Form

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    Product Categories

    Tags:

    Aromatic Dicarboxylic Acid Polyester Monomer Polymer Intermediate Resin Intermediate

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