PVC Additives Knowledge

A rigid PVC formulation is five decisions, not a shopping list: a heat stabilizer that sets the thermal ceiling, a lubricant balance that controls fusion and metal release, a processing aid for fusion and melt strength, an impact modifier for finished-part toughness, and a filler for cost and stiffness. Start from the symptom, not the additive name — most "we need a processing aid" requests turn out to be a lubrication or stabilizer problem.

• Discoloration, burning, or a narrow processing window

  Heat stabilizer problem. Every other additive works inside the thermal ceiling the stabilizer sets, so review it before changing anything else.

• Plate-out, die build-up, high torque, sticking

  Lubrication balance — internal versus external lubricant ratio. Adding a processing aid here masks the symptom and can make plate-out worse.

• Late or incomplete fusion, poor melt strength, surface defects

  Acrylic processing aid territory, but only once the lubrication balance has been reviewed.

• Brittle failure of the finished part in service

  Impact modifier: acrylic core-shell for weatherable outdoor profile, MBS where clarity matters, CPE where cost dominates indoors.

• Compound cost, stiffness and dimensional stability

  Calcium carbonate grade and surface treatment, balanced against impact loss at higher loading.

• Anti-block / Slip Masterbatch — Film Blocking Together or Feeding Poorly

  Freshly wound film sticks to itself, or converted bags do not open or feed through packaging machines.

• Anti-fog Masterbatch — Fog or Water Droplets Inside Greenhouse or Food Packaging Film

  Water condenses as droplets inside greenhouse film (blocking light) or food packaging film (blurring product view and dripping onto food).

• Anti-static Masterbatch — Static Electricity on Plastic Film or Parts

  Plastic parts or film hold a static charge — attracting dust, sticking, or creating ESD risk in electronics packaging.

• Desiccant Masterbatch — Bubbles, Streaks, or Splay When Processing Regrind or Wet Resin

  Regrind or hygroscopic-contaminated resin produces bubbles, silver streaks, or splay marks in the finished part, and drying is not practical or sufficient.

• Flame Retardant Masterbatch — Plastic Burns or Fails a Flame Rating

  A plastic part must pass a flame-rating standard (e.g., UL 94 V-0, glow-wire, FMVSS 302) and the base resin fails.

• Laser-Marking Masterbatch — Cannot Laser-Mark on Dark or Colored Plastic

  A part needs a permanent, high-contrast laser mark (barcode, batch code, logo) and the base resin does not respond — the mark is faint, blurred, or invisible.