Anyone ever heard of Polyaspartic topcoat? - The Garage Journal

Very weary of Companies offering zero VOC 100% aliphatic polyurea.Correct me if I'm wrong Alpha or Wolverine, but 100% Polyurea is sold to manufacturers and then the manufacturers add their own ingredients to create their own formula and rename it Polyaspartic. From my experience, the higher the solids count the faster it cures and the harder it is to use. So for DIY systems, it has to be thinned out like crazy just to be workable to the average Joe, no? Please educate us.

Not exactly... but close. Yes, there are many companies that do very little of their own formulating with these products. But, what manufacturers are calling a polyaspartic and what manufacturers are calling a polyurea are different. The polyaspartic is technically a type of polyurea that adds a polyaspartic acid ester (diamine) the mix. A polyurea is basically the reaction of the "B" side of a urethane (the isocyanate containing portion) with the "B" side of an epoxy (amine). The polyaspartic is the reaction of an isocyanate with a polyaspartic acid ester containing diamine resin. People use the word polyaspartic to differentiate between a urethane (Polyol + Isocyanate) or a polyurea (Amines that do not contain polyaspartic acid + Isocyanate).

The polyaspartics are a bit difficult to use and make look good. The main benefit is the cure speed and return to service time. You will see many manufacturers saying that they are more durable but that is VERY relative to what they are comparing it to. If you are comparing it to a 'big name brand' epoxy or urethane that has a taber abrasion resistance of only about 50 then it may be more durable. However, if you're comparing against our EnduraShield than has a Taber abrasion resistance of 9mg then... it's pretty hard to beat that.

The difficulty in application is that the Polyaspartic Acid Ester system is very moisture sensitive. Too much and the stuff is curing on your roller covers... too little and you don't get the same results you want. Now, some manufacturers are trying to add oxizolidine moisture scavengers to even out the cure. We found out early in development that it's a bad idea. It turns out that these moisture scavengers promote yellowing... doh...

Polyaspartic refers to a polyurea that has a slower cure time and is moisture cure (most of the time). It has nothing to do with adding solvents/VOC's or other ingredients and renaming it, it has to do with the chemical reaction. However, there are some polyaspartics that contain maybe 1% or so solvents. Typically, polyurea resin mixes with isocyanate and dries in less than 4 seconds. You probably are already familiar with these types, they are used as spray-on truck bedliners. They are also solvent/VOC free but are not moisture cure.

Both polyureas and polyaspartics can cure in seconds. The cure speed has nothing to do with the definition. Polyaspartics can contain pretty much any concentration of solvents. We've seen formulations from 0% to 73% of solvent... so... 27% to 100% solids. You guys may remember the guy from Florida who posted on here about getting chemical asthma. He was using a 75% solids polyaspartic. His formulation from a big name company skinned on top during application since the moisture in the air made the surface react quickly. The 'skin' trapped the solvent (25% PM Acetate) which leeched out of the coating over time to give him chemical asthma.

While there are polyureas that cure in a few seconds there are also polyureas that are formulated to have long potlifes and cure times as well.

Hopefully Fred/Alphagarage and the Wolverine guy will not lobby to get me kicked off the message board here, but I've been researching for hours a day for the better part of a week and I think I'm ready to pull the trigger on the Rock Solid stuff. $300 a kit covers 250 sqft. I will need 4-5 depending on what I want to do, hopefully I can get a group buy together and save some coin.

Are you kidding me... boy have you got us wrong. When you walk up to us and punch us in the nose for no reason we don't try to get you kicked off the board... we... uhhh... well... we petition the UN to kick you off the planet. But first, we send someone to break your thumbs... then your legs... and... uh... uh... we burn your house down... ummm... and... all your friends' houses get burned down... and.... ummm.... we shoot 'em. lol...

No Fred not directed at you in any way or form, sorry it came across that way. And your right we have never had any dealings, I think the freight would probably eat me up if I were to purchase coatings from y'all. But if it were tax free for Texas then maybe it would wash out.

I was referring to a couple of manufactures up north that like to send spam e-mails to contractors...what a beating. Would never and will never purchase from them.

Awww... Fred can take it... stick it to 'em... lol...

To be honest we have not been pushing Polyaspartic (EnduraShield ) at all. The only time we would ever sell it is if we needed an aliphatic clear that absolutely had to be dry in a couple of hours. Otherwise, most applicators have switched to our EnduraShield . Although this is a urethane it is very quick curing for the amount of potlife you get. Plus... it's pretty hard to beat for abrasion resistance. While it should not be applied too thick... that never seems to be a big problem since most people can't afford to put Polyaspartics on thick anyway.

We are probably not going to ever sell Polyaspartic to the DIY market. While I never say never... I will say... the technology would have to improve SIGNIFICANTLY.

But... my advice for the brave DIYer...

1) Make sure you are not allergic since your throat can close up and you can die. This is the best reason to work with a friend. And, while your at it... spend $40 on a good respirator and organic vapor cartridge.

2) Know your humidity, potlife, and temperature.

3) Do NOT use solvent based Polyaspartics.

4) Do NOT use PA that contains oxizolidines (promotes yellowing).

5) Watch your humidity!

6) Have LOTS of roller covers... and... don't cheap out here! Get the best non-shedding roller covers you can.

7) Watch your humidity... and... the dewpoint...

8) Don't drop sweat in the bucket... or cry... or spit...

9) Hire a professional... (threw that in for garageguy... but... seriously... consider this for Polyaspartics!)

10) Watch your humidity...

Been fun hangin' with you guys for awhile... but... gotta run...

That's actually incorrect. A polyurea does not contain an epoxide group. Also, it's typical that the "A" side is the isocyanate (hardener) and the "B" side is the polyol resin.

First, I'm assuming that you are a resourceful person who is trying to learn. My response here is not designed to hurt your ego or boost mine. Sometimes it's hard to know what someone is trying to communicate since we don't have the advantage of non verbal cues typing on forums. I'm assuming the best of you and hope that you are giving me the same benefit of the doubt.

Whatever is the 'A' side or the 'B' side is not always the same from manufacturer to manufacturer. That is why I spelled out the chemistry... which is what matters.

If you Google Polyol A or Polyol B you will find plenty of people do it both ways. However, I would say that the largest portion of manufacturers call the Isocyanate portion the B side.

The 'B' side of an epoxy is almost always an amine (or other reactive component that does not contain epoxy)... The 'A' side of an epoxy is typically the actual epoxy resin. That is why I spelled out which side I was calling the amine.

The important thing is that a Polyurea is the reaction of an Amine and an Isocyanate... just like I said.

If you read it again you'll notice that I never said that a polyurea contained any epoxy (although I'll touch on that a little more again later)... I specifically spelled out that a polyurea is an Isocyanate and an amine. Most of the time it is a specific type of amine... a polyetheramine. These can have varying chain lengths and molecular weights.

It is also very difficult to generalize chemistry these days. Almost everything we make is some kind of hybrid. Now, although I never said that polyureas contained epoxide groups... then can. In fact, we have a new formulation that contains epoxy, Isocyanate, Acrylic Monomer, and Amine... all in one hybrid. We're not even sure what to call it yet! I guess it's an AcryliPoxyUrea.

Polyaspartic acid Names Other names PASP Identifiers

• -40-6 (poly-L-aspartic acid)

ChemSpider

• none

CompTox Dashboard (EPA) Properties (C4H5NO3)n Molar mass variable Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Chemical compound

Polyaspartic acid (PASA) is a biodegradable, water-soluble condensation polymer based on the amino acid aspartic acid.[1][2] It is a biodegradable replacement for water softeners and related applications.[3] PASA can be chemically crosslinked with a wide variety of methods to yield PASA hydrogels.[4] The resulting hydrogels are pH-sensitive such that under acidic conditions, they shrink, while the swelling capacity increases under alkaline conditions.[4]

Goto Think-Do Chemicals to know more.

Sodium polyaspartate is a sodium salt of polyaspartic acid.

In nature, PASA has been found in as fragments of larger proteins with length up to 50 amino acids,[5] but as of had not been isolated as a pure homo polymeric material from any natural source.[6] The first isolation of synthetic oligomeric sodium polyaspartate, obtained by thermal polycondensation of aspartic acid, was reported by Hugo Schiff in late 19th century.[7] Later it was proposed that thermal polymerization process leads through polysuccinimide intermediate.[8][9] Polyaspartic acid is produced industrially in both the acid form and as the sodium salt.[2]

Properties and structure

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Due to presence of carboxylic groups it is polyelectrolyte with anionic character. Naturally occurring PASA fragments consists of α,-linked L-aspartatic acid.[5] In contrast, the repeating unit of synthetic polyaspartic acid may exist in four isomeric forms, depending on the stereochemistry of starting material (D- and L-aspartic acid) and synthetic procedure leading to α and β links. Due to the protein-like backbone (presence of amide bond in the backbone), PASA has suitable biodegradability.[2]

Synthesis

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Many different routes lead to PASA. In the simplest[10] and the oldest approach[6] aspartic acid is heated to induce dehydration. In a subsequent step the resulting polysuccinimide is treated with aqueous sodium hydroxide, which yields partial opening of the succinimide rings. In this process sodium-DL-(α,β)-poly(aspartate) with 30% α-linkages and 70% β-linkages[11] randomly distributed along the polymer chain,[12] and racemized chiral center of aspartic acid is produced.[13] There were many catalysts reported for improving thermal polymerization method. Main benefits from their application is increasing of the conversion rate and higher molecular weight of the product.[14][15] Polyaspartic acid can also be synthesized by polymerization of maleic anhydride in presence of ammonium hydroxide.[1][2][16] High control over repeating unit isomers can be achieved by polymerization of N-carboxyanhydride (NCA) derivatives,[17] by polymerization of aspartic acid esters[18] or by application of enzyme catalyzed reaction.[19] Pure homopolymers, D- or L-PASA with α- or β-links only, can be synthesized using those methods.

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The polymerization reaction is an example of a step-growth polymerization to a polyamide. In one procedure, aspartic acid polymerizes at 180 °C concomitant with dehydration and the formation of a poly(succinimide). The resulting polymer reacts with aqueous sodium hydroxide, which hydrolyzes one of the two amide bonds of the succinimide ring to form a sodium carboxylate. The remaining amide bond is thus the linkage between successive aspartate residues. Each aspartate residue is identified as α or β according to which carbonyl of it is part of the polymer chain. The α form has one carbon in the backbone in addition to the carbonyl itself (and a two-carbon sidechain) whereas the β form has two carbons in the backbone in addition to the carbonyl itself (and a one-carbon sidechain). This reaction gives a sodium poly(aspartate) composed of approximately 30% α-linkages and 70% β-linkages.[2]

Applications

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Polyaspartic acid and its derivatives are biodegradable alternatives to traditional polyanionic materials, in particular polyacrylic acid.[20] PASA has ability to inhibit deposition of calcium carbonate, calcium sulfate, barium sulfate, and calcium phosphate and can be used as an antiscaling agent in cooling water systems, water desalination processes, and waste water treatment operations.[21] In addition and due to its ability to chelate metal ions, it provides corrosion inhibition.[11] It can also be used as biodegradable detergent and dispersant for various applications.[22]

PASA also has a variety of biomedical applications. Its high affinity with calcium has been exploited for targeting various forms of drug-containing carriers to the bone.[2] The main component of bone is hydroxyapatite (ca. 70%) (mineralized calcium phosphate). Apart from bone targeting, PASA has been modified for other biomedical applications such as drug delivery, surface coating, DNA delivery, mucoadhesion, and beyond.[2]

As it can be synthesized in an environmentally friendly way and is biodegradable, polyaspartate is a potential green alternative to several materials such as sodium polyacrylate used in disposable diapers and agriculture.[23][24][25] It can act as a super-swelling material in diapers, feminine hygiene products, and food packaging.[26] The level of water uptake which is inversely related to the mechanical properties of the hydrogel can be tuned by changing the crosslinking density.[4]In addition to its industrial uses, solid-state NMR studies have shown that poly‑aspartate can integrate into amorphous calcium carbonate (ACC) nanoparticles, adopting α‑helix conformations that significantly stabilize the ACC phase and delay its crystallization. Moreover, NMR relaxation data reveal that structural water molecules within ACC undergo millisecond-timescale 180° flips, suggesting that dynamic hydration plays a crucial role in the stabilization mechanism.[27]

See also

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• Polyaspartic esters