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Study on physical properties and causative factors of froth vs. pour foams, highlighting issues such as solubility, flammability, density distribution, and environmental impact. Analyzes factors affecting foam performance and cost-effectiveness.
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A Comparison of the Physical Properties [&Their Causative Factors]of Froth vs. Pour Foams CPI 2008 - San Antonio John Murphy Foam Supplies, Inc
Why Froth? • Perceived Molding Advantages • Can foam in cooler mold, • Less Tight mold needed • Higher initial viscosity • Better Flow? • Less Shrinkage? • Better Thermal Conductivity? • Better Density Distribution?
Same Formulation 3 BAs Low pressure equipment -15ppm Lanzen Mold Compare Solubility Reactivity Density Economics Control Packing Mold Temp Orientation Monitor Free Rise Density Flow Dens Gradient Cell Orientation The Study
Froth Agents • Solubility, Lambda worsen → • Environmental improves • Flammability issue w 152a
Liquid BAs • Solubility, Lambda worsen → • Environmental issue w 245fa • Flammability issue w HCs, ecomate?
Flammability • Ecomate less flammable than HFC-152a, HCs • FSI Ecomate PU systems are rated as COMBUSTIBLE, not flammable. Do not require Red Label • Hydrocarbon Blended Systems are FLAMMABLE!
Drop in formulation • Optimized for R-22 • BA Drop-in • On Molar basis • No Catalyst adjustments • Lanzen Mold [2000 x 200 x 50 mm] • 80 F and 95 F • 20 min demold • Vert & Horz
Minimum Fill Density • Formula optimized for Froth • HIGH Level of Amine Polyol to counter Evaporative Cooling • Causes Liquid BA foams to lock-up prematurely • Therefore will have high MFD ! • Reformulated w/o Amine polyol • Still Not Optimized • → Normal MFD !
Minimum Fill Density • Similar Flow w Each BA
Minimum Fill Density • MFD high [3.0-3.2 pcf] – :.No End Shrinkage • Used unblended Isocyanate • Fear of incompatibility w some HFC blends • Fewer Blends to make • MFD is a measure of FLOW • Similar Flow w each BA
Density Distribution • Uniform distribution is desired • Panels cut into 10 equal pieces [A to J] • Long direction – fill end to vent end • Densities determined • Results graphed
Effect of Orientation • Vertical - Densifies more at end of rise
Temperature Effect • Warmer mold gives lower density
Temperature Effect • Warmer mold = lower density • True for Froth & Liquid BAs • WHY? Less BA Loss • Lower Formula COST • Better for Environment • :. Use Warm Molds
R-22 DISTRIBUTION • Packing increases DENSITY • Does NOT improve DISTRIBUTION
R-134a DISTRIBUTION • Warmer Temp = Lower Density
Density Distribution • Density Distributions – equivalent! • Packing • Increases Density • Doesn’t improve Distribution • Optimization can improve Distribution • All formulations need optimization!
Cell Orientation across Panel • Even with uniform Density Distribution • Cell orientation is Important • Affects Physical Properties • Compressive strength • Thermal conductivity • Dimensional Stability • Should be uniform across panel
CELL ORIENTATION I WIDTH B E LENGTH • Measured Compressive Strength • [on SECTIONS B, E, I ] • In Panel Length, Width, & Thickness directions • Independent of Pour Orientation
Economics • Fluorochemicals ALWAYS more Expensive • Cost depends directly on the # F added • 2C HFCs require >68 wt% F to be non-flammable • Higher MOLE Wt adds to formulation expense • Lambda NOT related to F content, MW • Ecomate superior λ, MW, Cost, Environmental • Cost not tied to Petrol prices
Environmental • Froths CONTAMINATE more than Liquids • [~6-8% LOSS for Froth vs. ~3-4% for Liquids]
Environmental • Froths CONTAMINATE more than Liquids • [~6-8% LOSS for Froth vs. ~3-4% for liquids] • Use Approx 2X more than ecomate
Environmental • Froths CONTAMINATE more than Liquids • [~6-8% LOSS for Froth vs. ~3-4% for liquids] • Use Approx 2X more than ecomate • Higher GWPs than ecomate
Environmental • Froths CONTAMINATE more than Liquids • [~6-8% LOSS for Froth vs. ~3-4% for liquids] • Use Approx 2X more than ecomate • Higher GWPs than ecomate • Ecomate Saves ~ 1 metric Tonne CO2 e • Per pound Ecomate used to replace 134a or 245fa
Conclusions • Temperature Effect • Warmer mold = lower density • True for Froth & Liquid BAs • WHY? Less BA Loss • Lower Formula COST • Better for Environment • :. Use Warm Molds • Why use Froth, when: • Liquids perform as well or Better in heated molds • Liquids Cost LESS
Conclusions • Similar Properties – Liquid or Froth • Flow [MFD] - Same • Dimensional Stability – No Issues • Density Distribution - Equivalent • Cell orientation - Same • Froth foams are more expensive • Both in real cost and cost to environment • Ecomate use can save 1 MT CO2 e / lb