# Lo w P re ssur e 2K SPF Kits

UNIQUE CHALLENGE S RELA TED T O BL OWING AGENT ADAPT AT IONS JUNE 6, 2014 CPI L OW PRESSURE WO RK GR OUP

### Fo am kit t echnology Applications Import ance of shelf life Chemis try consider ations Summary Conclusion 

# Outline

# The Ne xt T

woSlides Gr aphic ally Illus trate B asic 2 Componen t Lo w P re ssur e (LP) SPF Kit Te chnology DEFINITION OF A “LOW PRESSURE 2 COMPONENTS PF KIT” Spray polyurethane foam (SPF) products that are pressurized to < 250 psi during manufacture and are sold in pressurized containers as two parts or components (2K) (A side & B side), also referred to as 2K- LPKits.

### 2K **Low Pressure SPF Foam Kits** 

**isocyanate** • 134a

• A- component

**polyol blend**  • B - component 

# A B • 134a Blow ing agent must be partially soluble in the liquid A & B side components

Blow ing agent is the sole propellant. Also maintains proper A/B ratio. 150 - 200 psi

# 2K Low Pressure **SPF Foam Kits polymer**  After mixing the polyol blend and isocyanate, polymerization begins in the gun nozzle with the blowing agent acting as the propellant and foaming agent A & B must be on ratio Mixing Nozzle

# Ty pic al Applic at ions of 2K LP Kits

◦ Used for air sealing and insulation in commer cial and r esiden tial construction (ne xt slide..) ◦ Po rt ability of kits enables their use on difficult - to - re ach jobsites

◦ High rise commercial construction ◦ In - field pipeline insulation in g as and oil transport ◦ Small, tight spaces, i.e. roof/wall junctures in commercial building renovation ◦ Also used in other indus tries such as mining and tr ansportation (cold stor ag e)

6Ty pical Energy- Saving Application Areas for 2K Low P ressure SPF Kits

# Special Ar ea of Concern: Shelf Lif e 2K Low Pr essur e SPF is sold thr ough dis tribution The kits mus t ha ve at least one year shelf life because: ◦ They ar e tr ansported to distribution center s and outlets acr oss the US & Globally ◦ They r emain in dis tribution channels for 1 – 6 months ◦ Con tr act or s often use kits 1 – 6 months after pur chase ◦ Con tr act or s lea ve them on jobsites for e xt ended periods befor e use Kits can be e xposed to elev ate d temper atur es (> 80F) during tr ansportation, stor ag e or end - use in hot climatesLow GWP blowing agents ar e designed t o br eak apart in the atmospher e

◦ The only known alternativ e blowing agent, Solstice GBA (ak a 1234z e, tr ans 1,3,3,3 - tetr afluor opr opene), contains a carbon - carbon double bond ◦ The carbon double bond is the site of attack for UV r adiation, which ultimately leads t o a low GWP This carbon double bond is particularly susceptible to atta ck by the tertiary amines used t o catalyz e SPF Br eak down of the blowing agent within the pack ag ed pr oduct cr ea te s chain re actions, r esulting in poor shelf life 

# Chemis try Considerat ions R eg ar ding Alt erna tiv e Blowing Ag en ts

# Sols tice GB A, ak a 1234z e carbon - carbon double bond

# Con tinued.. In 2K low pr essur e SPF pr oducts, temper atur e & pr essur e c ombine to acceler ate chemical re actions within the foam cylinder s ◦ Low pressure SPF pr oducts ar e pr essuriz ed t o 150 – 200 psi during manufactur e ◦ This pr essur e for ces the molecules in the B - side blend to “inter act ” with each other mor e quickly than at atmospheric pr essur e (i.e. in drums tha t ar e not pr essuriz ed until use) ◦ Str ongly basic tertiary amines ar e utiliz ed in all forms of SPF to catalyz e foam’ s A/B r eaction ◦ These amines ar e s tr ong enough to affect Sols tice GBA’scarbon - carbon double bond, especially under pr essur e ◦ Re sults in unpr edictable B - side chemical r eactions

# Re sults of Shelf Lif

e T es ting The inher en t pr essur e c ontained within the 2K LP pr oducts, coupled with ex posur e of the kits to e xc essiv e heat during tr ansportation, stor ag e, and use, can cr ea te a mild “pr essur e cooker ” en vir onmen t, which potentially leads to unwanted chemical r eactions 134a is a v ery s ta ble molecule under these conditions To da te , low pr essur e manufactur er s ar e obser ving shelf liv es much less than one year ◦ Re placing 134a with Sols tice GBA in curr ent formulations r esults in appr ox . 2 – 8 week shelf life in s tandard manufactur er testing* ◦ Sols tice GBA is NOT a dr op - in solution *manufactur ers collectiv e observ at ions

# Summary Due t o the unique natur e of 2K low pr essur e SPF pr oducts, manufactur er s will re quir e a long er time fr ame than high pr essur e SPF supplier s when con ve rting to alt erna tiv es. The only known alternativ e g aseous blowing ag en t for low pr essur e SPF pr oducts, 1234z e, pr esen ts serious challeng es r ela te d to shelf life. The amoun t of R&D time needed to ov er come this issue is unpr edict able. In addition, low pr essur e SPF manufactur er s also face the same challeng es as High Pr essur e SPF with r eg ar ds to pr oduct testing r equir emen ts and time fr ames.* * Ma y 20, 2014 pr esentation by CPI to EP A Snap Office

# Conclusion Low pr essur e manufactur er s will need to r eformulate and test all formulations fo r shelf life s ta bility – the known alternativ e is not a dr op in, and appear s to contribute to unwanted and irr eversible r eactions in the pr oduct The curr en t alternative g aseous blowing ag en t is unpr ove n in an y commer cial application, and giv es unaccept able re sults in low pr essur e manufactur er ’s te st ing Ther e is a need for additional blowing ag en t options A z er o GWP pr oduct solution can be achiev ed giv en the pr oper amount of time and suitable alternativ es

# CPI Low Pre ssur e Work Group Con ve nience Pr oducts Dow Pr oducts Fo mo Pr oducts, Inc. RHH F oam Systems