Bio-based Resins for Coatings

In recent years, there has been a growing interest in the use of bio-based resin building blocks in the synthesis of polymers for use in coatings. Bio-based products are derived from plants and other renewable agricultural, marine, and forestry materials and provide an alternative to conventional petroleum derived products.

Driving forces include a growing public and private awareness and interest in the use of renewable raw materials that can meet sustainability expectations and certifications such as Green Seal and Green Guard as well as the USDA BioPreferred Program for product labeling. Green Seal and Green Guard are environmentally driven, whereas the USDA BioPreferred Program functions to encourage the use of renewable agricultural raw materials in products. ASTM d6866 was developed to standardize, certify and classify the bio-based content of materials. Minimum renewable carbon content categories (MRCC) have been established for purchasing by Federal agencies and their contractors.

Table I – BioPreferred Coatings Categories[1]

resin1

Bio-based resins for coatings are normally referred to as alkyds (EU). Alkyds are comprised of fatty acid modified polyester resins. These resins are sometimes modified to include a urethane (EU) linkage and thus called uralkyds or oil modified urethanes. The fatty acid portion is derived from naturally occurring or renewable oils derived from sunflower (EU), safflower,soybean (EU), castor (EU), tall (EU) and others. Polyesters (EU) are derived from the reaction product of a polyol (EU) and a di or multifunctional acid or carboxylic acid and anhydride (EU) to form multiple ester linkages in a polymer chain.

 

To read the full article written by Ron Lewarchik, Chemical Dynamics President, on UL Prospector, click here.

Paint Cost Calculations

Paint Cost Calculations

How to Get the Most Mileage Out of Your Paint

Determining the effective cost of paint that can be made from naturally occurring elements involves several issues that must be considered. These include the volume solids of the paint, application method, and the geometry of the object to be painted. For example, a paint that sells for $20 per gallon at 20% volume solids is actually more expensive on an applied cost basis than a paint that sells for $40 per gallon at 45% volume solids.

Theoretical coverage

 =

Volume Solids

Dry mils required

 

To illustrate the cost of paint to apply one mil (0.001 inch) per 100 square foot of the $20 paint is as follows:

  • If a gallon of paint weighs 10 pounds and is $20/gallon at 20% volume solids = 10# of the 20 $/Gallon X 0.20 pounds of volume solids = 2.0 pounds of solid or dry paint per gallon of liquid paint for $20. Accordingly the cost of each dry pound of paint is $10. The square foot coverage of a paint is 1604 square feet per mil at 100% volume solids. Since our paint is 20% volume solids, at one mil dry film thickness, one gallon of paint will cover 1604 square feet/mil X 0.20 % volume solids = 320.8 square feet/gallon at a cost of $20. Accordingly the cost to paint 100 square feet of surface is $20 X 100/320.8 = $6.23

To illustrate the cost of paint to apply one mil (0.001 inch) per 100 square foot of the $40 paint is as follows:

  • A gallon of this paint weighs 12 pounds and is $40/gallon at 45% volume solids = 12# of the 40 $/Gallon X 0.45 pounds of volume solids = 5.14 pounds of solid or dry paint per gallon of liquid paint for $40. Accordingly the cost of each dry pound of paint is $7.78. The square foot coverage of a paint is 1604 square feet per mil at 100% volume solids. Since our paint is 45% volume solids, at one mil dry film thickness, one gallon of paint will cover 1604 square feet/mil X 0.45 % volume solids = 721.8 square feet/gallon at a cost of $40. Accordingly the cost to paint 100 square feet of surface is $40 X 100/721.8 = $5.54

 Accordingly, in this illustration, the $40 paint provides more value than the $20 paint as it provides lower cost coverage at equal dry film thickness. The table below illustrates paint coverage per mil for paint applied at 100% volume solids. 

 

Theoretical coverage

 =

Volume Solids

Dry mils required

Price of Paint Breakdown

New US Patent on Rust Coatings Granted

US Patent on Coatings that Arrest Rust Granted to Chemical Dynamics LLC

US Patent 8,927,649 was awarded to Chemical Dynamics LLC on January 6, 2015. US Patent 8,927,649 covers of a film forming penetrant coating with a high cross-link density that arrests corrosion on rusty substrates.

Patent Abstract: A one part, storage stable polymerizable formulation is provided that includes an ethenically unsaturated polymerizable compound intermixed with a free radical polymerization initiator and an organic solvent. The organic solvent provides storage stability and upon evaporation of the solvent, the rate of polymerization of the compound accelerates independent of addition of a second part. The formulation includes at least 30 total weight percent solids upon cure. Optional additives to the formulation include at least one of a cure accelerator, a filler, a plasticizer, a colorant, and a cure inhibitor. A process for forming a polymerized coating on an article involves the application of this formulation to the substrate of an article and allowing sufficient time for the solvent to evaporate to form the polymerized coating on the article. The substrate of the article forms a corrosion barrier even without prior removal of a native corrosion layer on a surface of the substrate of the article.

Paint Raw Material Evaluation

SITUATION: A global company with multibillion dollar sales required a paint raw material evaluation from a paint expert of the performance and application potential of a new fluoropolymer resin that they developed.

ACTION: Due to the resident coating expertise in fluoropolymer coatings, the supplier contracted Chemical Dynamics to provide an independent evaluation of this new resin chemistry. Our company conducted paint and coatings testing to evaluate the material.

RESULT: Chemical Dynamics completed the evaluation and identified multiple new applications for the fluoropolymer resin chemistry.