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Factors contributing to k-factor optimization with eco mate ® blown foams CPI Orlando 2007. How does ecomate compare?. How does ecomate compare in Foams ?. Handmix Pours Comparison Molar Substitution - in same formulation Same Index Same Surfactant amount Same Catalyst amount
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Factors contributing to k-factor optimization withecomate®blown foams CPI Orlando 2007
How does ecomate comparein Foams ? • Handmix Pours Comparison • Molar Substitution - in same formulation • Same Index • Same Surfactant amount • Same Catalyst amount • Same molar BA content
BA Molar Substitution2” thick sample, 75 ºF • Handmix Data ONLY • Results are Relative • ECOMATE ~ same as 245fa • k NOT SOLELY dependant on MW 0.187 0.202 0.204 60 134 117
Thermal Conductivity • Not dependant solely on: • Molecular Wt • Gas λ • K-Factor at standard conditions • Depends on many additional factors, including: • Temperature • Processing • Formulation • Configuration • Protection
Examine Processing Effects • Hand Mix Factorial Design • Examine • Mix Time • Mix Speed • Pour Size • Surfactant Concentration
Mix Time Mix Speed Pour Size Surf. Concentration Not significant Faster = lower λ (less BA loss) Larger = lower λ (less surface area) More = lower λ (less BA loss) PROCESSING EFFECTS:Handmix Results Summary
Handmix v MachineSame ecomate Formulations • Machine ALWAYS Superior ! K FACTOR
Examine Formulation Effects • Polyol • Type and Amount • Catalyst • Surfactant • Type and Amount • Blowing agent • Temp Effect • Loss / Diffusion • Blends
Examine Polyol Effects • In a Hand Mix Factorial Design • Vary POLYOL BLEND • Hold Constant • Catalyst • Surfactant • Blowing Agent • INDEX = 120
Polyol Effect: DENSITY 25 – 75% 0 – 50% 0 – 25% • EDA faster, • - Captures more BA • - Thus Lower Density
Polyol Effect: THERMAL Props EDA worse ! Strong affinity for BA Less in vapor space
Polyol Results • Choice of Polyol Critical - • Not only affects Physicals • Faster reactivity captures more BA • Polyol Type can also affect k-factor, λ
Speed of reaction Cell Orientation Blow v Gel Cats Gel / Rise Ratio Examine Catalyst Effects
Gel Time EffectsFaster = Lower k PU Expo2002, pg 459, fig 12
Cat Effects: STRETCHED RISE Gellation Slower Faster SMALL, _|_ RISE BEST Orientation
Speed of reaction Cell Orientation Gel / Rise Ratio Faster is better Smaller, rounder better Gel at Rise best Catalyst Effects Results
Surfactant Effects • AFFECTS • Cell formation • Polyol / ISO compatibility • Strut / window thickness • Cell Windows open / closed • Fineness of Cells • Density • TYPE –Critical ! • Mol Wt • Siloxane content • Degree of modification • See Degussa Paper [ref 4] • AMOUNT –very important • Optimize for each formulation
Molecular Weight Influential, not critical Examine BA Effects
Molecular Weight Gas λ Value Influential, not critical Influential, not critical Examine BA Effects
Molecular Weight Gas λ Value Solubility = Viscosity Influential, not critical Influential, not critical Very Important on Flow Examine BA Effects
Molecular Weight Gas λ Value Solubility = Viscosity Flow = Cell Orientation Influential, not critical Influential, not critical Very Important on Flow Critical to Thermal Properties Examine BA Effects
Molecular Weight Gas λ Value Solubility = Viscosity Flow = Cell Orientation Vapor pressure Influential, not critical Influential, not critical Very Important on Flow Critical to Thermal Properties Very Important Examine BA Effects
Molecular Weight Gas λ Value Solubility = Viscosity Flow = Cell Orientation Vapor pressure Liquid v Gas Influential, not critical Influential, not critical Very Important on Flow Critical to Thermal Properties Very Important Measure k at Use Temp Examine BA Effects
Liquid v Gaseous BA • GAS • Advantage of potential lower thermal properties • Lost because of higher Vapor Pressure • More Gas escapes during foaming
Caveat • Moisture • Very poor insulator • Very small molecule [MW=18], • Smaller than N2 [MW=28, 78%], • Smaller than O2 [MW=32, 21%] • Ubiquitous • Penetrates foams readily • Plays havoc with K-factor
Diffusion • Gases want to reach equilibrium
DiffusionIF POROUS • Graham’s Law Rate1 M2 = Rate2 M1 Water 3X greater Diffusion ! Rigid Foams NOT Porous ! Fick’s Law: Solubility Factors BA H2O
Blowing Agent LossAHAM Study • Negligible!
REAL LIFE EXAMPLES • BEST EVALUATIONS • Run side-by-side • Use Actual CABINETS • Use Actual Conditions • Measure • Energy used • Ice melt over time • Compressor cycles, or • Temperature change w time
BTU LOAD TEST – Refrigerated Display case, Maintain 40F 141b 245fa ecomate 18% more energy 20% more energy CONTROL ecomate, 245fa nearly same
DUTY CYCLE – 39” VENDOR CABINETS 5-100 watt bulbs to keep 95F 40 F CHILLER 40 F CHILLER 245fa ecomate %Time ON for 95 F: %Time ON for 95 F: 37.4% 36.8% ecomate, 245fa nearly same !
BLENDING BAs • Ecomate very compatible • Why spend extra money?
Handmix v MachineSame ecomate Formulations • Machine ALWAYS Superior ! • Ecomate machine k values respectable K FACTOR
Thermal Conductivity • Not dependant solely on: • MW • Gas λ • K-Factor at standard conditions • Depends on many additional factors, including: • Formulation • Processing • Configuration • Protection
Conclusions • Thermal Improvements available • Thru formulation • Thru processing • Protect foams from Moisture • Ecomate nearly equals 245fa • in Hand mix data • in Side-by-side Performance Tests • Compare for Yourself!