DIMETHYL CARBONATE (DMC)

The Newest VOC Exempt Solvent

Kowa American CorpMarch 2011

Previous VOC Exempt Coating Solvents

• Realistically there were only a handful of VOC exempt solvents that are not HAPS (or ODS) and under $ 2.00/lb that formulators can use for coating, cleaning & adhesive solvents:

• Acetone• Methyl acetate (MeAc) • tert-Butyl Acetate (tBAc)• p-Chlorobenzotrifluoride (PCBTF)

Dimethyl Carbonate (DMC)

• VOC exemption petition filed July 2004 by Kowa American Corp.

• DMC has perhaps lowest MIR value of any liquid chemical in commercial use based on studies conducted by Dr. William Carter (study funded by Exxon Mobil Chemical)

• Ultra-low MIR is allowing for fast approvals by the various states due to its very favorable ozone reduction potential

DMC & PC recently exempted by the EPA

• Dimethyl Carbonate (DMC) & Propylene Carbonate exempted by EPA on Jan 13, 2009

• Each state must also exempt DMC & PC for stationary source VOC rules.

• Almost all states beside California will have exempted DMC by mid 2011 (45 states have now exempted DMC (March 2011)).

• California must have each of their Air Districts separately exempt DMC for coatings, Inks and adhesives, which is proceeding forward.

DMC for Architectural, Aerosol & Automotive Refinish Coatings• DMC is VOC exempt in all states today

except parts of California & Mass. for: Architectural Coatings (subpart D),

Automotive Refinish Coatings (Subpart B) and Consumer Items (subpart C) based on Federal VOC rules (40 CFR part 59)

• DMC (with its ultra low MIR value) can be used in aerosol coatings in Calif. (soon to be approved for all of USA for aerosol coatings).

DMC VOC Exempt StatesWashingtonMarch 2011

OregonMay 2010

CaliforniaEach AMD must exempt

Nevada

IdahoMarch 2010

UtahMarch 2010

ArizonaMay 2011?

Montana

TexasApril 1, 2010

NewMexico

AlaskaDec. 2010

Hawaii

Colorado

WyomingOct. 2010

NebraskaJune 2010

OklahomaJuly 2010

KansasSept. 2010

North Dakota

South DakotaJune 2010 Michigan

May 2011

WisconsinAugust 2010

Minnesota

Iowa

MissouriDec. 2010

ArkansasJune 2011

Louisiana

IndianaIllinois

Ohio

KentuckyTennesseeAugust 2010

AlabamaMarch2010

Florida

Georgia

South CarolinaNov. 2010

North Carolina

Virginia

WestVirginia Maryland

Delaware

Pennsylvania

Maine

New Hampshire

Vermont

Rhode Island Sept. 2010New YorkDec 2010

Connecticut

New Jersey

Massachusetts May. 2011

Green states are VOC Exempt

DMC Exemption Status in Calif.• San Diego, Santa Barbara, Monterey Bay,

Mohave, Butte ,Ventura, Colusa & Feather River AMD’s have exempted DMC as a VOC

• Most “county” AMD’s plan to exempt or have no VOC rules (functionally exempt)

• San Joaquin Valley Air MD expected to exempt by May 2011.

• Shasta, Glenn & Tehema AMD’s may already exempt DMC depending on application

• Santa Barbara users must file for a permit

DMC Exemption Status in Calif.

• Bay Area AQMD (San Francisco area) looking at when they can begin rulemaking for exempting DMC in 2011

• SCAQMD (L.A. area) has deferred rule making indefinitely, for more info: Naveen Berry, 909-396-2363, nberry@aqmd.gov

• SCAQMD may need to look at certain coatings applications such as car refinishing and in plant coatings to exempt first.

SierraNevadaColusa

Solano

Napa

ContraCostaSan Francisco

SanJoaquin

Sonoma

Lake

SanMateo

SantaCruz

SantaClara

Alameda

SanBenito

Monterey

Merced

Fresno

Mono

Kings

Butte

Inyo

DelNorte

SantaBarbara

LosAngeles

LassenShasta

Siskiyou

San Bernardino

ImperialSan Diego

Modoc

Plumas

Glenn

El DoradoAlpine

Amador

Marin

Kern

RiversideOrange

Trinity

Yolo

Tuolumne

Tulare

San LuisObispo

Ventura

Tehama

Green = DMC VOC Exempt orFunctionally Exempt/ no VOC rules (no restrictions on use of DMC)

Light Green = permit or application for individual variance required

Light Blue = In rulemaking

Tan = no formal rulemaking yet

California CARB Consumer items• CARB regulates “consumer product” applications

(coatings are covered by each AQMD separately)• Paint thinners is in their “multi-purpose solvent”

classification (some local Calif. AMD’s debate that CARB can regulate paint thinners over them)

• CARB needs typical formulations for non-coating consumer applications using DMC, including the solvent the DMC will replace for CARB to do a health hazard assessment. CARB Contact: Carla Takemoto 916-324-8028, ctakemoto@arb.ca.gov

MIR Reactivity Values (2009)MIR gram basis MIR mole basis

DMC 0.055 4.95

Ethane 0.26 7.8

Acetone 0.35 20.3

Methyl Acetate 0.067 5.2

Prop Carbonate 0.27 27.56

Benzotrifluoride 0.28 40.91

DMC General Properties

• DMC is a colorless, fast evaporating solvent• Has substantial polar nature, and moderate h-

bonding strength effective in replacing esters, glycol ethers and ketones in formulations

• Has low toxicity, an unobjectionable methanol type odor and low skin irritation

• Freezes at 2 – 4 ºC (36 –38 ºF)• Flammable Liquid, Flash point 17 ºC (63 ºF)

DMC Structure

CH3 O C O CH3

O

DMC Evaporation Rate

Fast to moderate evaporation rate (3.22 –3.4, BuAC = 1.0), similar to tBAC (2.8), toluene (2.0) and isopropyl acetate (3.0)

Can be used to as slightly slower evaporating replacement for MEK (3.8), Ethyl Acetate (4.1- 4.2), or as faster evaporating replacement for IPA (1.7), MPK (2.3), Ethanol (1.8) and MIBK (1.6)

DMC - Flammability

• DMC has a flashpoint of 63ºF (17ºC)• Flammability will limit use in consumer

coatings, cleaning or indoor applications• Flammability risk still much lower than

acetone (-4º F), ethyl acetate (26ºF) or MEK (26ºF), which DMC can readily replace

• Partially water soluble (up to 13 % in water), which allows water to be more effective in fighting DMC based fires.

Flashpoint, E. rate, Boiling point Evaporation Rate BuAc =1.0

Flashpoint ºF

Boiling point ºC

DMC 3.22 63 90

PCBTF .9 109* 139

Acetone 5.6 -4 56.5

Prop Carb <.005 269.6 240

tBAc 2.8 40 98

BTF 2.8 54 102

DMC Solubility Properties

• Hildebrand solubility parameter 20.3 Mpa• Hansen solubility parameters: Dispersion

15.5 polar 3.9 h-bond 9.7 molar vol. 84.2• Similar solubility parameters to some

common glycol ethers: cellosolve acetate, ethylene glycol butyl ether acetate, propylene glycol monobutyl ether and propylene glycol monoethyl ether acetate

DMC Solubility Properties

DMC has been described as useful in acrylics, urethanes, epoxies and alkyd systems.

DMC is miscible with almost all organic solvents

DMC would easily replace oxygenated solvents like esters, ketones & glycol ethers

DMC can replace alcohols, aromatics and aliphatics with appropriate co-solvents and/or reformulation work

DMC in Waterborne Systems• DMC being an ester, can hydrolyze in

acidic and basic conditions to methanol and carbon dioxide.

• DMC may be stable in neutral conditions with suitable buffers, although formulators need proper care to prevent CO2 build up

• DMC’s primary usage area should be in all solvent borne systems, where residual water does not normally cause hydrolysis issues

DMC Expected Uses• DMC has shown promise in Auto refinish,

with its favorable solubility, odor, evaporation rate and economic profiles

• Industrial coatings for coating parts and architectural components at factories have shown similar appeal.

• Also used in traffic paints, steel drum linings, floor coatings, concrete sealers

• Can also be an effective paint thinner & multipurpose solvent, as is or as co-solvent

DMC’s Odor Profile• One of DMC’s most favorable properties is

a mild and non-offensive odor.• PCBTF and Tert-Butyl Acetate odors are

much more pronounced and pungent• Noxious solvent odors are perhaps the most

important concern of neighbors to body shops, factories, print shops and other industrial settings

• Mild odor is well received by workers handling DMC or used in their work areas

DMC Cost & Supply• DMC pricing is just below $ 1.00/lb,

making it price competitive with most oxygenated solvents except possibly acetone.

• Drums and bulk isotanks readily available from multiple factories in China. DMC is used in very large volumes in China for coatings primarily because of its low cost.

• Totes can be filled from isotanks.• Long term a bulk tank in USA is possible

DMC – Toxicity• DMC (like all methyl esters) rapidly de-

esterifies in the body to methanol & CO2 • DMC has low acute oral toxicity (LD50 rat

12,900 mg/Kg, LD50 mouse 6,000 mg/Kg)• DMC was found to be negative in mutagenic

tests (in vitro Ames & comet assay) • Readily biodegradable and has low potential to

bio-accumulate or be persistent in environment • Not expected to be toxic to fish or bacteria

(possibly toxic to algae)

DMC & Methanol toxicities• EPA feels teratogenicity is major endpoint

health concern of environmental exposure for Methanol (and therefore DMC)

• DMC is not mutagenic or genotoxic• Well run study by Exxon/Mobil on DMC’s

teratogenic potential confirms it is virtually identical to Methanol’s (NOEL 1,000 ppm)

• Kowa recommends an 8 hour industrial PEL of 100 ppm based on DMC’s toxicity profile

California OEHHA Assessment

• California's Office of Environmental Health Hazard Assessment issued a toxicity assessment of DMC in Dec.2009 that used the toxicity of its primary metabolite methanol and existing DMC studies to issue a toxicological assessment of DMC

• Reported there were no concerns that DMC like methanol would be carcinogenic

Calif. OEHHA Conclusion• OEHHA report concluded that doses levels

of DMC likely to be achieved by environmental exposures to the general public by inhalation appears to have “relatively minor” environmental health concerns

• Established interim acute and chronic REL, where the acute REL is identical to MEK’s and the chronic REL similar to Isopropanol’s

DMC Azeotropes & Co-solvents• There have been a few cryptic references in

literature to DMC forming azeotropes with numerous solvents without further data

• Azeotropes using DMC could be the “wild card” in developing coating or cleaning formulations, substantially changing the evaporation rate, solubility and perhaps flammability profiles (to over 100 °F ?)

• Using DMC & PC together might replace PCBTF, Xylene, butyl acetate, aromatic 100

Propylene Carbonate

• Propylene Carbonate is a very slow evaporating solvent (evaporation rate <.005, BuAc =1). This will restrict its solvent use.

• Low viscosity 2.4 cps, high flashpoint 253º F• Practically non-toxic by oral, dermal or

Inhalation, slight skin irritant, eye irritant• Available from Kowa from same Chinese

source as our Dimethyl Carbonate.

Propylene Carbonate • Propylene Carbonate’s very low toxicity

profile allows it’s use in cosmetic products, therefore PC safe for all consumer items

• Readily biodegradable• Useful as a co solvent, wetting agent or

tailing solvent (last solvent to evaporate).• Literature suggest can be used in binary &

tertiary solvent systems to replace common solvents like trichlorethane and toluene

BENZOTRIFLUORIDE - BTF• Proposed VOC exempt solvent, EPA

recently tabled petition due to recently revised MIR values in 2009

• Low MIR of 0.28 (2009) should shortly be allowed for aerosol coatings on federal level, now allowed in Aerosol coatings in Calif. with a MIR value of .26 (2004 table)

• Almost a direct replacement for toluene, similar solvency and evaporation rate (2.8)