Flexible PVC Technology (seminar outline)
Flexible PVC Technology -? Flexible (PLASTICIZED) PVC Seminar
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?Factors Affecting Stabilizer Choices for Flexible PVC Applications.
???? Formulating, Compounding, Processing
?Reference Index:
?Formulation Components:
Plasticizers:
Fillers:
Lubricants:
Pigments:
Foaming Agents:
Miscellaneous Components:
Compounding:
Major Markets for PVC
Stabilization of Flexible PVC (Non-Lead)
Stabilizer Performance in Flexible PVC (non-lead)
End-Use, and Lifetime of Product:
Formulation Components:
?PVC Resins-- Characteristics (incl. VC/VA copolymers)
?Suspension (& Bulk), Emulsion (Dispersion)
?Extrusion Plastisols / Organosols
?Calendering Coating, Casting
?Molding (Injection) Molding (Rotational, Slush)
?Fluid Bed Dipping
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?Important parameters:
????? K-Value, Particle morphology, Plasticizer Dry-up, Plastisol viscosity, Zinc sensitivity, Electricals.
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Plasticizers:
?Primary Secondary Specialty
?Phthalates Cl- Paraffins (FR) Epoxy Oils & Esters
?Trimellitates Hydrocarbon extenders Phosphates (FR)
?Adipates Polymeric Esters
?Azelates
?Sebacates
?(Alcohol Choices: Branched or Straight-chained C-8, C-9, C-10’s)
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?Plasticizer Efficiency (vs. 50 phr DOP): Fusion, Solvation, Gelation, Tensile,
?Elongation, Clarity, Viscosity (initial & aged), Air release, Low Temperature
?Flexibility (cold-crack), Volatility (automotive fogging), Permanence (oil & water extraction & spew).
?Use Levels: Shore A&D Hardness.
?Effects upon heat stability and special stabilizer needs (Phosphates & Cl-Paraffin)
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Fillers:
?Ground, Precipitated Calcium Carbonate (most commonly used)
?Particle size, Distribution (Top size and Fines)
?Affects tensile, elongation, viscosity
?Use level (capacity of resin/plasticiser system to accommodate)
?Affects above properties, and hardness, abrasion resistance, and stabilizer optimization (Zn levels)
?Other fillers used:
?Silicates: Clay, Kaolin, Talc, and (formerly) Asbestos
?Barytes - Ba sulfates
?ATH - Aluminum Trihydrate (FR)
?Al/Mg Minerals? Ultracarb (FR)
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Lubricants:
?Stearic acid, Stearyl Alcohol, Ca Stearate, EBS, GMS, GMO, and other Fatty Esters.
?Oxidized PE wax, Paraffin wax, Mineral oil
?Concerns: Effects upon Clarity, Heat sealing, Printability.
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Pigments:
?Inorganic, Organic Types
?Concerns: Heat stability, U.V. stability, Oxidative stability, Chemical resistance.
?Specialty pigments:
?Metallics (Al, Cu, Au, Bronze powder) - Stabilizer adjustments
?Fluorescents - Stabilizer choice
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Foaming Agents:
?Endothermic (Na carbonate/ citric acid blends)
?Exothermic Azodicarbonamide-- (most commonly used)
?Factors affecting blowing temperature and rate of gas release:
?Particle size, metal carboxylate (Zn, K, Pb, Ba, Sn) activation retardation.
?Other exothermic CBA’s: OBSH, TSH
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Miscellaneous Components:
?Wetting Agents (Viscosity control)
?Anti-fog Agents (Film)
?U.V. Absorbers
?Biocides
?Antistatic Agents
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Compounding:
?Dryblend -------------- (direct) -------------->> Powder molding
?Fluid bed
?Extrusion (incl. foams)
?Compounding extrusion -- (direct feed) --> Calendaring
?Supported
?Unsupported
?Foams
?Pellets -------------------------------------------> Injection Molding
?Extrusion
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?Banbury (Melt Mixer) ---> 2 Roll Mill ---> Calendaring
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?Plastisols & Organosols
?Low Shear Mixer (Planetary or Hobart type) or...
?High Shear Mixer ( Cowles Dispersion)
?Vacuum De-aeration for both --------------> Coating, Casting (Knife, Reverse Roll)
?Molding (Rotational, Slush)
?Dipping
?Foams on all.
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?Processing: (All can be foamed)
?Extrusion (Mostly single screw, 20-30:1 L/D)
?Vented - for Dryblends
?Non-vented - for Pellets
?Profiles, Tubing, Hose, Film, Sheet, Medical Products
?Calendaring (Inverted “L” or “Z” types)
?“Supported” (Paper/ Fabric Substrates) Film & Sheet
?Wall covering, Upholstery, Automotive, etc.
?“Unsupported” Film & Sheet
?Pool & Pond Liners Roofing Membranes, Shower Curtains, Flooring,?Molding
?Misc. Specialties, Toys, Shoes & Soles, Powder (rotational) Molding ?for Automotive Instrument Panels
?Powder Fluid Bed Coating
?Dishwasher and Refrigerator Racks & Shelving, Closet Shelving
?Plastisols (Pastes) and Organosols
?Coating & Casting
?Film, Flooring, Fabric Coating, Paper Coating, Metal Coating
?Molding (Rotational, Slush)
?Balls, Inflatables, Dolls, Boots, Prosthetics, Novelties (i.e. Lures)
?Dipping
?Tool Handles, etc.
领英推荐
?Vinyl Solutions (in MEK, etc.)
?Homopolymer and Copolymer (for adhesion)
?Baked Coil Coating (Appliances), Can Lining, Aluminum Siding
?Vinyl Emulsions (Latices)
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Major Markets for PVC
Building & Construction...
- Pipe & Fittings (Potable water, sewer, irrigation, telephone duct, fiber optic cable duct, drain/waste/vent, spiral wound large diameter culvert, chemical and food processing piping, fire sprinkler piping)
- Siding, Gutters, Downspouts
- Window Profiles
- Fencing
- Decking/Docking
- Flooring & Cove Base
- Wall Covering
- Wire & Cable
- Single Ply Roofing Membrane
- Landfill Liners
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Transportation...
- Instrument Panels, Dashboards
- Auto, Mass Transit & Aircraft Interiors & Seating
- Under Hood Wiring
- Under Car Abrasion Coating
- Floor Mats
- Arm Rests
- Foamed Gaskets
- Window Trim
- Body Side Molding
- Convertible rear windows
???? (Obsolete! but big years ago!)
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Electronic/Appliances...
- Keyboards
- Component Housings
- Electrical Cord Jacketing
- Fiber Optic Sheathing
- Floppy Disk Jackets
- Various Components in Phone Systems, Power Tools, Washers, Refrigerators, Air Conditioners, Computers.
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Medical...
- Blood Bags, and Tubing
- Catheters
- Surgical Gloves, and Sheeting
- Prosthetics
- Single Dose Medication Packaging
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Packaging...
- Meat and Produce Film
- Jar Lid Gasketing (Foamed Plastisol)
- Clear Blister Pack Sheet (Thermoformed)
- Clear & Opaque Bottles
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Home & Leisure...
- Garden Hose
- Toys, Dolls, Inflatables
- Shoe Soles
- Fishing Lures
- Vinyl Coated Metal Racks & Shelving
- Boat & Dock Pads
- Tarpaulins
- Credit Cards (copolymer)
- Patio Furniture, Fabric, Strapping
- Shower Curtains
- Swimming Pool Liners
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Stabilization of Flexible PVC (Non-Lead)
?Typical Stabilizer Components, and Their Functions:
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?Barium Nonyl Phenate (& overbased versions)
?Long term stability in mixed-metal systems, Balances Zinc Component.
?Cadmium Carboxylates (octoate, neodecanoate, etc.)-- Usage disappearing.
?Early & mid-range color hold, U.V. stability
?Zinc Carboxylates (octoate, neodecanoate, etc.)
?Good early color, poor long term stability due to “Zn burning” caused by buildup of ZnCl2, a strong Lewis acid and degradation accelerator.
?Also a good “Azo” activator. Balanced usage necessary. Higher filler contents benefit from higher zinc levels.
?Calcium Carboxylates
?Long term stability (not as good as Ba). Offsets “Zn burning” in nontoxic systems.
?Beta-di-ketones (& newer organics via Ackros)
?Used as Cd replacements in Ba/Zn and Ca/Zn systems - very costly!
?Alkyl/Aryl Phosphites (DPIOP, PDDP, TNPP, PE Phosphites)
?Heat stability and 2ndary AO (peroxide decomposer)
?U.V. stability
?ZnCl2 de-activation (chelation?)
?Polyols (PE,etc) & Phenolic AO’s
?Zeolites & Hydrotalcites
?Very efficient HCl scavengers, works well with mixer metal & tin systems.
?Epoxys- Soya, Linseed Oils, Tallate esters
?Good HCl scavengers, adds to “synergy” of most mixed metal systems.
?Alkyltin Carboxylates, Mercaptoesters
?Specialty uses ( Ultra high clarity, pigment considerations)
?Mixed Solvents & “compatiblizers” (Polar to non-polar types, surfactants)
?Used at a minimum to obtain stable blends having good shelf life through freeze/thaw/heat cycles.
?????? Goal is to strive for minimum volatility and maximum active ingredients concentration that is shelf-stable.
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Stabilizer Performance in Flexible PVC (non-lead)
?Factors of Concern / ?During Processing:
?Color Hold, including Regrind use
?Plateout Control ( Emboss Retention, Surface Integrity)
?Lubricity/ Rheology (Especially with high speeds & thin gauges)
?Plastisol Viscosity & Air Release
?Low shear- Brookfield
?High shear- Sievers
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End-Use, and Lifetime of Product:
?Clarity
?U.V., Outdoor Durability
?Long Term Heat Aging (i.e. 150-200 deg. F for weeks)
?Toxicity
?Electricals
?Stain Resistance (Sulfide, Urethane, U.V. Absorber, Antioxidant)
?Odor
?Moisture Resistance - Hydrolysis ( see also Clarity)
?Heat-sealing, Printability
?Volatility (Automotive “Fogging”)
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The above factors need to be considered when designing the stabilizer(s) for specific products and processes, or when selecting an existing stabilizer for that product or process.
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