Ready-Mix Joint Compounds Using Non-Uniformly Substituted Carboxylmethylcellulose
The presently disclosed and claimed inventive concept(s) relates generally to a carboxymethylcellulose (CMC) system for use in ready-mix joint compounds. More specifically, the presently disclosed and claimed inventive concept(s) relates to a non-uniformly substituted (“blocky”) CMC system for use as an efficient thickener and rheology modifier for ready-mix joint compounds and the use of a reduced amount of clay for improving the joint compounds.
1 . A ready-mix joint compound comprising a binder, a non-uniformly substituted CMC, a filler, water, a biocide and an attapulgite clay.
2 . The ready-mix joint compound of claim 1 , wherein the density of the joint compound is about 7 to about 11 pounds per gallon (ppg).
3 . The ready-mix joint compound of claim 1 , wherein the density of the joint compound is about 12 to about 15 pounds per gallon (ppg).
4 . The ready-mix joint compound of claim 3 , wherein the attapulgite clay is present in the amount from about 0 to about 1.25 wt %.
5 . The ready-mix joint compound of claim 3 , wherein the attapulgite clay is present in the amount from about 0 to about 1.9 wt %.
6 . The ready-mix joint compound of claim 2 , wherein the attapulgite clay is present in the amount from about 1.25 to about 1.75 wt %.
7 . The ready-mix joint compound of claim 2 , wherein the attapulgite clay is present in the amount from about 0.6 to about 2.0 wt %.
8 . The ready-mix joint compound of claim 1 , further comprising a non-ionic thickener.
9 . The ready-mix joint compound of claim 8 , wherein the non-ionic thickener is selected from the group consisting of methylhydroxylethyl cellulose (MHEC), hydroxyethyl cellulose (HEC), hydroxymethyl hydroxyethyl cellulose (HMHEC), and ethylhydroxyethyl cellulose (EHEC), hydrophobically modified hydroxyethylcellulose, hydroxypropyl methylcellulose (HPMC), hydroxypropyl guar and derivative guar, and combinations thereof.
10 . The ready-mix joint compound of claim 1 , further comprising an anionic thickener.
11 . The ready-mix joint compound of claim 1 , further comprising a citric acid.
12 . The ready-mix joint compound of claim 1 , further comprising a chelating acid or a chelating acid salt.
13 . The ready-mix joint compound of claim 1 , further comprising a chelating agent.
14 . The ready-mix joint compound of claim 1 , further comprising an aluminium ion.
15 . The ready-mix joint compound of claim 11 , further comprising an aluminium ion.
16 . The ready-mix joint compound of claim 1 , further comprising a polyvalent cation.
17 . The ready mix joint compound of claim 11 , further comprising a polyvalent cation.
18 . The ready-mix joint compound of claim 1 , wherein the binder is selected from the group consisting of polyvinyl alcohol, ethylene vinyl acetate latex, poly(vinyl acetate) latex, starch, casein, polyacrylamide, and copolymers of acrylamide and acrylic acid.
19 . The ready-mix joint compound of claim 1 , wherein the filler is selected from the group consisting of calcium carbonate, calcium sulphate dehydrate, dolomitic limestone, and combinations thereof.
20 . The ready-mix joint compound of claim 1 , wherein the biocide is selected form the group consisting of 2[(hydroxymethyl)amino]ethanol and 1,2-benzisothiazolin-3-one.