Residential concrete densifier and sealer?

[cluelesswanderer]

Hello! I have absolutely no background in the sciences / chemistry, so I thought maybe you folks could help dumb it down for me. I am renovating an old house and just got new concrete poured in the basement. I want to polish the floors and leave them uncovered for environmental and health purposes. I don’t want any vinyl or other unnecessary finishes. Just a concerned and conscious mom of a toddler lol.

The contractor who does the diamond polishing in this case says he needs to add a densifier, which is a lithium silicate nano particle based product.

The manufacturer indicates that the product once cured has the PH level of 11-12 and is highly anti bacterial naturally because of this. Here are the exact words from one of their literature materials:

“The technology used to make “said product” makes it alkaline by nature. The typical pH of our 100% mineral coating is 11.5 to 12.

Even when it is applied on the floor for long-time, the pH of the dried surface will remain high. Once it is on contact with water or humidity it will produce OH- ions. These in turn will affect the growth of any microorganism preventing on the floor surface.
One of the direct consequences of that is the odor control property of “said product”. It can also reduce chances of cross contamination in areas like clinics, Hospitals, Schools and airports.

Since the “said product” coating is 100% mineral and has a crystalline structure. When cured, the molecular arrangement of billions of pointy crystals forms a micro sand paper like surface (fig.-1). These formed clear and transparent crystals reflect 100% of the light generating shine to the floor without absorbency.“

I have three concerns which I am hoping a chemist can address:

1. Does the fact that this product contains nano particle lithium silicate create any health issues after the product has cured? For example, walking on the flooring, a baby crawling on it in the long term, any dust particles arising from the polished concrete floor, etc (inhalation / skin contact)?

2. What does it mean when the company indicates the PH level is 11-12? What does this mean for residential safety of occupants who spend many hours at home and on or near the finished floor that contains this product, albeit cured? Are there any health concerns here due to the chemical nature?

3. The contractor also says that a sealer can be applied, but I am not at all familiar with the composition and whether it is a safe and non toxic option? It contains these “ingredients.”

N-(3-(trimethoxysilyl)propyl)ethylenediamine
Alcohols, C14-15, ethoxylated .Alpha.-Tridecyl-.Omega.-Hydroxy-, Phosphate, Ammonium Salt

Thanks everyone. Really hoping to get some insight. I can share the product name and SDS for both densifier and sealer I just don’t know if that’s permitted here.

 

[berkeman]

Welcome to PF.

I want to polish the floors and leave them uncovered for environmental and health purposes. I don’t want any vinyl or other unnecessary finishes. Just a concerned and conscious mom of a toddler lol.

When cured, the molecular arrangement of billions of pointy crystals forms a micro sand paper like surface (fig.-1).

You want your toddler crawling and walking around on bare/cold cement? Um, please rethink that.

A better question would be something like "I will be installing carpeting in our wonderful new basement, and would like to understand what sealant treatments would be best to apply to the concrete before installing the carpeting".

 

[cluelesswanderer]

Floors have heating system installed under the concrete, and we will also have lovely large area rugs, so that’s not the concern. I’m focusing on the densifier and sealer to make sure there are no health and safety concerns.

 

[DaveE]

Next step - Ask the manufacturer for the MSDS for that product (or search the web for it yourself). That's what it's there for.

 

[cluelesswanderer]

I’ve attached the sheets. Again, it’s hard for someone with no science background to make out the safety of the ingredients. Do they offgas, are the nano particles a concern? SDS sheets rarely address any of these questions which are a little more in depth about whether something is toxic long term. They address best practices during application mostly. What about long term? Hence I am asking here.

 

[berkeman]

I’ve attached the sheets.

The upload doesn't look like it worked. Use the "Attach files" link below the Edit Window to upload PDF copies of the MSDSs, or you can also just post links to the MSDSs at each manufacturer's website. Thanks.

 

[DaveE]

I don't know that anyone here can tell you what is safe or not. That is ultimately a personal decision. Obvious hazards should be spelled out clearly in the MSDS*. More subtle concerns, like outgassing or nano particles are virtually impossible to document. It is likely that no one knows if it hasn't been carefully studied.

Some people buy organic eggs, because they are safer than the non-organic ones. Others don't think it matters compared to other risks they take, like driving your car to buy eggs.

*PS: Also note that the MSDS will also include hazards for the people manufacturing and applying the product. It isn't uncommon for things to be hazardous to work with but safe once installed. Like oil paint, or fluorescent lights for example.

 

[hutchphd]

The concrete in my 80 yr old basement/lab/workshop is pretty damned dense.
I believe the appropriate question is how much does this cost? I assume there is some marginal benefit. The question is cost/benefit.

 

[Tom.G]

The concrete in my 80 yr old basement/lab/workshop is pretty damned dense.

That is expected, concrete continues to densify (become harder) with age over many years at least.

One reference is at: (long article; search for 'harden" in it)
http://matse1.matse.illinois.edu/concrete/prin.html

(above found with:
https://www.google.com/search?q=long+term+hardening+of+concrete)