Curing agent for paint

Latex Paint Drying Time Vs. Curing Time

Although this type of corrosion may sound detrimental and usually isthere are instances where this naturally occurring process is encouraged and used. Here we'll take a look at bimetallic corrosion in-depth. A curing agent is a substance that is used to harden a surface or material. It is typically applied to polymer surfaces to facilitate the bonding of the molecular components of the material.

The stronger the molecular bonds are, the harder the material surface is.

curing agent for paint

There are three types of curing agents, namely: curing ag ents that react with the surface upon which they are applied to facilitate hardening; catalytic ag ents that do not react with the material surface; and initiator ag ents that only beg in the necessary hardening reactions but do not continue to react with the system. Toggle navigation Menu. Home Dictionary Tags Coatings.

Curing Agent Last Updated: July 11, Recommended Content. Bimetallic Corrosion Basics Although this type of corrosion may sound detrimental and usually isthere are instances where this naturally occurring process is encouraged and used.

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How to Reduce Epoxy Curing Time

Definition - What does Curing Agent mean? Corrosionpedia explains Curing Agent There are three types of curing agents, namely: curing ag ents that react with the surface upon which they are applied to facilitate hardening; catalytic ag ents that do not react with the material surface; and initiator ag ents that only beg in the necessary hardening reactions but do not continue to react with the system.

Share this:. Related Terms. Related Articles. Where can I find a coating that is chloride and sulfur corrosion-resistant? Are there any OSHA regulations that need to be taken into account when using thermal insulating coatings?

With respect to CUI, how well do thermal insulating coatings retard the spread of corrosion? More of your questions answered by our Experts. Related Tags. Synonyms: Hardener. Connect with us. Popular Resources.

Sponsored by: Graco Inc. View Now. Sponsored by: GPT Industries. Provided by: Corrosionpedia. Coating Failures and Defects Guide. View All Webinars. View All Downloads. Downloads provided by Corrosionpedia.A series of high-reactive powder coating polyesters offering innovative solutions for low-temperature curing or for reduced baking cycle time has been developed, which will allow penetration into new applications. This reduction in cure temperatures is bringing a new innovative approach to novel applications and optimized process efficiency while keeping high performance.

The objective of this article is to present the findings that demonstrate those achievements. This means that the total oven residence time needs to be only min to completely cure the reactive powder.

The total oven residence time is minutes. One can understand that very heavy steel elements take a significantly longer time to heat up.

For such very heavy substrates the benefit of a shorter oven residence time is even more desirable.

curing agent for paint

To be noted: high oven temperatures offer much quicker heating up rates, which means one can reduce the residence time significantly. The polyester developments were done for four different types of hardeners used for powder coating technology, including:.

Our chemists faced several challenges that could have easily impeded the goal of lowering the cure temperatures and shortening the cure times. We found that reactive polyesters would allow clients to formulate powders with lower curing temperatures: e. This discovery grants new possibilities for powder application on heat-sensitive substrates and heavy objects, while also saving energy costs and facilitating the coating operation. These discoveries also open up various opportunities for our target groups, as shown in Table 1.

This polyester is suitable for smooth finishes. There are other polyesters in the same family that are suitable for formulating textures or showing improved scratch resistance. Other high-reactive polyesters are even tin-free. The resin family comprises a list of different resin grades Table 2. In Figure 2, one can see the film Tgs of some low-bake hybrid polyesters on 0.

The indicated time is always the total residence time in oven. The over-baking resistance, i. IR curing results in some instances is worse than with convection oven curing. This can be expected as the energy density of IR is much higher and can easily provoke more yellowing if the energy dose is not applied precisely. This reaction cannot be accelerated by catalyst.

Paint Treated Wood--Tips and Tricks

Crucial parameters, which do not allow further reduction of curing temperature for this hardener, include:. The yellowing of the powders depends to a large extent on the concentration of the HAA in the formulation. IR curing is with most polyesters not possible, as the film shows degassing issues due to the release of H 2 O. Besides the gloss retention there are many other properties to overcome. In addition to the full range of colors, including metallic pigmentations, the market desires a full range of different gloss levels.

High-gloss, glossy and semi-gloss finishes are formulated with single polyesters in combination with suitable fillers and additives. For semi-matte and matte finishes, a dry-blend system, i. Reactive polyesters for all gloss levels are available. Additionally, there are other reactive HAA polyesters with other features for architecture class 1 applications available Table 4.

These new polyesters also enable the powder coating industry to not only increase its productivity, but to introduce innovative solutions and improved sustainability items into the market. I want to hear from you. Tell me how we can improve. This website requires certain cookies to work and uses other cookies to help you have the best experience. By visiting this website, certain cookies have already been set, which you may delete and block.The solid state and associated particle size of said curing agents can be a limitation for certain manufacturing processes e.

Cured materials using such mechanisms typically suffer from brittleness and associated poor mechanical properties requiring additives and formulation to compensate for property degradation. These epoxy resin compositions exhibit high storage stability and provide cured products having good toughness properties, but the pot-life is not sufficient for all applications. Moreover the achieved storage stability is strictly dependent on the concentration of the curing accelerators making the balance between stability and reactivity difficult to achieve.

We have surprisingly found that providing protected base catalysts unexpectedly results in storage-stable IK epoxy resin compositions which allow processing over a longer period of time pot-life and rapidly produce cured products having outstanding mechanical and thermal properties. This disclosure proposes a system for obtaining different reactivities in an epoxy based composition by carefully selecting the acid to form a salt with a base or adducting the base with a protecting group.

Paint Dry and Paint Cure… Two Totally Different Things & A Lesson In Patience

The base is then activated by heating the composition to a pre-defined temperature. Such temperature depends on the protection mechanism used. A an epoxy resin containing on average more than one epoxy group per molecule.

Examples of epoxy resins suitable as component A are:. The reaction is preferably performed in the presence of bases. Examples of such polycarboxylic acids are oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid or dimerised or trimerised linoleic acid. Such amines are, for example, aniline, n-butylamine, bis 4-aminophenyl methane, m-xylylenedi amine or bis 4-methylaminophenyl methane.

It is preferable to use epoxy-containing compounds derived from mono-and poly-fatty acids having from 12 to 22 carbon atoms and an iodine number of from 30 tofor example lauroleic acid, myristoleic acid, palmitoleic acid, oleic acid, gadoleic acid, erucic acid, ricinoleic acid, linoleic acid, linolenic acid, elaidic acid, licanic acid, arachidonic acid and clupanodonic acid.

Within the scope of this disclosure, both the fully epoxidised oils and the partially epoxidised derivatives that still contain free double bonds can be used for component A. Preferred epoxy resins can also be obtained by the reaction of polyglycidylether and polyglycidylester with alcohols, such as diols.

The reaction with diols increases the molecular weight. However, addition of a component C to the above mixture can significantly lower the curing temperature and time without affecting the storage stability. Starting compounds for the preparation of component C may be, for example, aliphatic, araliphatic, aromatic or heterocyclic amines, guanidines and N- heterocyclic compounds which exhibit a pK a -value of conjugated acid greater than 7.

However, it is also possible to use the epoxy component or the hardener in more or less than the equivalent amount. The amounts used depend on the desired final properties of the reaction product as known by the skilled persons in the art.

Storage at low temperatures is not necessary. The addition of component C is performed shortly before application. This allows for extremely long pot-life combined with very fast curing at target temperature.

Ethyl cyanoacetate The mixture is stirred for 1 h at room temperature RT. Then vacuum ca.One of the advantages of latex paint over oil-based paint is that latex dries extremely fast. In a well-ventilated room, latex paint may dry within minutes after you put it on the wall.

At this stage, however, the paint is only superficially dry; until it cures, it is still fragile and it won't stand up to rigorous wear until weeks after application. Paint drying time is the amount of time it takes for the paint to be dry to the touch after application. For latex, drying time is relatively short compared to that of oil-based paints. You can apply additional coats of latex paint within a few hours after the surface dries. The paint, however, remains vulnerable to damage from wiping, washing or exposure to water or chemicals.

As latex paint dries, its solid components contact and adhere to each other, a process called curing. When fully cured, you can wipe or wash the paint surface without fear of harm, and the paint is much less vulnerable to damage by water or chemicals. Curing is a relatively long process that continues well after the surface of the paint dries to the touch.

Most latex paints feel dry within an hour or less after application in a room-temperature environment; you can typically apply a subsequent coat of paint in about four hours. In ideal conditions, latex paint takes about two weeks to cure to the point that you can wash it.

In less-than-ideal conditions, some paints may take up to 30 days to cure fully. Humidity, ventilation and temperature all affect the time that latex paint takes to dry and cure. In humid, poorly-ventilated or cool environments, the evaporation of water from the paint slows down, leading to relatively slow drying times.

At 50 degrees Fahrenheit, you'll have to wait about six hours before you can apply a second coat of paint. Low temperatures may also prevent the paint from curing properly.

Some paints will cure in temperatures as low as 40 degrees Fahrenheit, but in general, you shouldn't apply latex paint in a temperature below 50 degrees. Evan Gillespie grew up working in his family's hardware and home-improvement business and is an experienced gardener.

He has been writing on home, garden and design topics since Skip to main content. Home Guides Garden Soil Care.View More…. Today, productivity has emerged as a major driver, and innovation focuses on developing epoxy coatings that have greater application versatility while providing enhanced performance properties, such as dry speed, rapid recoat, and through-cure.

For marine and protective coatings, the need is for faster cure and blush-resistant coatings when applied under adverse, low temperatures conditions. In this sector, the drivers are to increase overall productivity with faster application of multiple layers coupled with lower bake temperatures which can provide energy savings.

This article will focus on the performance attributes of a novel polycyclic-aliphatic amine and its use in the development of new epoxy curing agents designed to provide benefit in the above markets. In addition, a review of model coating formulations and their key performance attributes, including the rapid recoat times, improved intercoat adhesion, and excellent corrosion protection properties will be discussed.

Global megatrends are reshaping the world we live in, driving common requirements of improved productivity and reducing costs, while addressing emerging environmental concerns. Epoxy coatings used in marine and protective coatings are based on either solid or liquid epoxy resins, derived from bisphenol A digylcidylether and cured in combination with polyamides or modified aliphatic or cycloaliphatic amine hardeners.

Typical modifications include amine adducts, Mannich bases, phenalkamines, and specialty ketimine curatives, 1 designed to ensure an optimum balance of handling and end performance properties. With the introduction of maximum volatile organic compound VOC limits in coating applications, development work in epoxy coatings has moved away from using traditional solid epoxy resins SER to systems based on the lower viscosity liquid epoxy resin LER.

Low-Temperature-Curing Powder Coatings System

A standard solvent-free LER has a viscosity of 10, mPa. This approach influences the handling and performance characteristics of the formulated coating.

Reaction kinetic studies demonstrate that there is a negative impact on the workable pot life coupled with an extension of the dry time. The latter effect is due to the polymeric network having to react and build up sufficient molecular weight to reach the gel point or dry-to-touch state, whereas with the SER systems, these are already high molecular weight polymers and dry-to-touch or lacquer dry is observed as soon as the solvents evaporate from the coating film.

Formulators can only use small quantities of this type of accelerator because a high concentration can result in driving the homopolymerization of the epoxy resin in favor of the preferred crosslinking reaction between the epoxy resin and amine curing agent. Excessive homopolymerization often results in brittle coatings and free unreacted amines, the presence of which may result in a decrease in the corrosion resistance properties of the cured film.

curing agent for paint

The amine is capable of enhancing the molecular weight build up in applied epoxy so coatings can reach their dry-to-touch state faster, while driving the crosslinking reaction so that coatings achieve rapid through-cure at both ambient and low-temperature cure conditions. This is evident when monitoring the degree of reaction via infrared IR spectroscopy. The Poly [HCA] shows a higher level of hydroxyl formation compared to the standard tertiary amine accelerator, which in the presence of liquid epoxy resin is shown to form ether linkages Figure 1.

High ether linkage formation is a clear indicator that the epoxy system undergoes homopolymerization rather than amine-epoxy crosslinking during the curing process. The novel polycyclic amine technology enables rapid property development when formulated with conventional polyamides, modified polyamides, aliphatic, and other formulated epoxy curing agents. The new polyamides undergo rapid cure, which enables application of topcoats based on similar epoxy or polyisocyanate technology within 15—30 min while maintaining excellent intercoat adhesion and corrosion protection.

It provides excellent film appearance without loss of gloss, distinction of image and surface wrinkling, and dive-back of topcoats into the primer. This performance attribute allows applicators to spray-apply multiple layers within quick succession, to increase the overall productivity of the coating application at the job site.

Although aliphatic amines such as DETA and TETA have high functionality and reactivity, they have a strong tendency to blush and form amine carbamate due to poor compatibility of the amine with the epoxy resin.

On the other hand, cycloaliphatic amines have excellent compatibility with epoxy resin because of the cyclocaliphatic backbones but have slower reactivity than aliphatics, especially at low temperature. Good compatibility between curing agent and epoxy resin is essential to provide coatings with good surface appearance, excellent overcoatability, and corrosion resistance. It has been a challenge in epoxy coatings to design a new amine building block that possesses the benefits of both the aliphatic and cycloaliphatic amines: the reactivity of an aliphatic amine and the resin compatibility of a cycloaliphatic amine.

As highlighted, Poly [HCA] is a novel polyheterocyclic amine that crosslinks with an epoxy resin delivering fast through-cure while maintaining good resin compatibility over a range of application temperatures.My first blog post of … Happy New Year!!!

Beyond frustrating right? Take a look what happened. For instance, if a client wants their furniture asap, I always explain the repercussions of using the furniture before it has had time to cure. To check if your paint is dry, touch an inconspicuous area with your finger. If the paint is not tacky and feels dry to the touch, it is dry.

To check if your paint is cured, do the fingernail test. In an inconspicuous area, press your fingernail into the paint. If it leaves an indent like my plate did…grrrr!!!

If no indent is visible and the surface is hard, your paint has cured. This was a wonderful article to read about dry and cure times. I just painted my living room hard wood floor with a porch and floor latex paint. Before I apply the clear polyurethane coats, do i need to let the paint cure or just dry. Hi Cindy! Hi john I am in the process of doing the exact same thing to my old living room wood floors.

I have painted them and now and getting ready to put on the polyurethane. Did you use a roller and how did your project turn out?

Do I need to wait for all the paint to cure before doing this? Hi TeeJay! I know this is an older post, but I hope you can help me with my question. Is there a fix for this, or will I have to completely strip it and repaint?

Hi Michele! If you are taking hot steamy showers that could slow the dry and cure time down. That said it may be beneficial to strip and repaint.A new generation of ketamine epoxy hardeners are technically outperforming their analogous predecessors both during and after cure. This article examines why their unique combination of long pot-life, reduced hazard and fast thin-film cure speeds make them the ideal curing agents for the paint and coatings industry.

Traditionally, ethylene amines have been used as epoxy curing agents and can cross-link epoxy resins to form an infusible mass. However, their poor compatibility with conventional aromatic epoxy, inherent toxicological properties and low active hydrogen equivalent weights with subsequent low stoichiometric loading levels negates their use in modern formulated systems.

Many modification techniques are employed to enhance their performance, including reaction with carboxylic acids to generate amido-amine and polyamides, mannich bases, association salts, adduction, and for applications requiring high latency and fast thin film cure, ketamines.

Ketamines are formed through the dehydration of a primary amine group with a ketone, as depicted in Figure 1. This grade was one of a small series of ketamines employed in the formulation of high-stability, two-pack epoxy systems.

These ketamines demonstrate stability, if not exposed to atmospheric moisture. As the reaction is reversible, when combined with the epoxy component and applied, the ketamine is hydrolyzed, liberating the functional amine and ketone components. The regenerated ketone is a volatile released from the film, and the original amine has active hydrogen groups that can react with the epoxy component in a conventional manner.

The product above is hydrolyzed to liberate ethylene diamine, which then in turn reacts with the epoxy. EDA is a relatively fast curing agent, but by generating the ketamine the reaction is retarded, requiring the hydrolyzation to occur before the epoxy-amine reaction proceeds.

Ketamines provide excellent pot-life while also retaining fast thin-film cure speeds, making them quite unique. The homologous series of ethylene amines with terminal primary amine groups, of which EDA is the basic member, allows a series of ketamines to be produced.

These products have offered some desirable performance properties, but the liberated amines are generally of a low molecular weight with high vapor pressures.

Concern over their toxicity and the costs attributed to REACH registration of each new ketamine species essentially led to the withdrawal of these conventional ketamines from circulation in Europe. This withdrawal and the resultant void in the marketplace led to Bitrez recently developing a new range of REACH-compliant ketamines to satisfy the market demand. The new series of ketamines are offered as solvent cut or solvent-free materials, although all of them liberate some solvent during the hydrolysis process.

First and foremost, the new series of ketamine grades was developed to be REACH compliant and available for use in Europe.

Additionally, improvements in the following properties were targeted. Looking at these target requirements, and using conventional grades and regulatory standards as benchmarks we can demonstrate the improvements made. Following the introduction of GHS, the threshold limits and reporting requirements for free monomer levels have been adjusted, and the escalating hazard rating for free DETA is as follows:.

The label requirements based on free monomers on supply is detailed in Table 1.


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