Mineral polymers and methods of making them
OwnerJoseph Davidovitsinventor
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Abstract
New mineral polymers called polysialates have the empiral formula M.sub.n [--(Si--O.sub.2 --).sub.z --Al--O.sub.2 --].sub.n,wH.sub.2 O where z is 1, 2 or 3, M is sodium, or sodium plus potassium, n is the degree of polycondensation, and w has a value up to about 7. The method for making these polymers includes heating an aqueous alkali silico-aluminate mixture having an oxide-mole ratio within certain specific ranges for a time sufficient to form the polymer.
Claims10
A polymer having a composition expressed in terms of oxides as follows:
- 1. 0.+-.0.2(yNa.sub.2 O,zK.sub.2 O):Al.sub.2 O.sub.3 :xSiO.sub.2 :wH.sub.2 O
- where, in the fully hydrated form, w is in the range of up to about 7, x is in the range of about 3.5 to about 4.5, and y and z have values such that the sum of y and z equals 1, said polymer having the following formula ##STR5## wherein n is the degree of polymerization, and said polymer having an x-ray powder diffraction pattern essentially that shown below:
- ______________________________________ Interplanar Spacing Relative Intensity (in Angstroms) of the Lines ______________________________________ 11.20 Broad and blurred 4.30 Middle strong 3.43 Strong 3.29 Strong 3.08 Middle strong 2.97 Middle strong 2.71 Weak 2.46 Weak 2.30 Middle strong 2.11 Weak 1.92 Very strong 1.81 Middle strong ______________________________________
A method for preparing a polymer having the formula ##STR6## wherein n is the degree of polymerization which comprises heating a sodium silico-aluminate/water mixture whose composition, in terms of oxide-mole ratios, falls within the following range:
- ______________________________________ Na.sub.2 O/SiO.sub.2 0.28 SiO.sub.2 /Al.sub.2 O.sub.3 4.02 H.sub.2 O/Na.sub.2 O 17.20 Na.sub.2 O/Al.sub.2 O.sub.3 1.14 ______________________________________
- said polymer having an x-ray powder diffraction pattern essentially that shown below:
- ______________________________________ Interplanar Spacing Relative Intensity (in Angstroms) of the Lines ______________________________________ 11.20 Broad and blurred 4.30 Middle strong 3.43 Strong 3.29 Strong 3.08 Middle strong 2.97 Middle strong 2.71 Weak 2.46 Weak 2.30 Middle strong 2.11 Weak 1.92 Very strong 1.81 Middle strong ______________________________________
A method for preparing a mineral polymer having the formula ##STR7## wherein n is the degree of polymerization which comprises heating a sodium and potassium silico-aluminate/water mixture having a composition in terms of oxide-mole ratios within these ranges:
- ______________________________________ (Na.sub.2 O,K.sub.2 O)/SiO.sub.2 0.25 SiO.sub.2 /Al.sub.2 O.sub.3 4.02 H.sub.2 O/(Na.sub.2 O,K.sub.2 O) 17.30 Na.sub.2 O/Al.sub.2 O.sub.3 0.8 (Na.sub.2 O,K.sub.2 O)/Al.sub.2 O.sub.3 = 1[,].0[.] K.sub.2 O/Al.sub.2 O.sub.3 0.2 ______________________________________
- said polymer having an x-ray powder diffraction pattern essentially that shown below:
- ______________________________________ Interplanar Spacing Relative Intensity (in Angstroms) of the Lines ______________________________________ 11.20 Broad and blurred 4.30 Middle strong 3.43 Strong 3.29 Strong 3.08 Middle strong 2.97 Middle strong 2.71 Weak 2.46 Weak 2.30 Middle strong 2.11 Weak 1.92 Very strong 1.81 Middle strong ______________________________________
A method comprising forming an alkali silico-aluminate/water mixture in which the oxide-mole ratios fall within the following ranges:
- ______________________________________ (Na.sub.2 O,K.sub.2 O)/SiO.sub.2 0.20 to 0.28 SiO.sub.2 /Al.sub.2 O.sub.3 3.5 to 4.5 H.sub.2 O/(Na.sub.2 O,K.sub.2 O) 15 to 17.5 (Na.sub.2 O,K.sub.2 O)/Al.sub.2 O.sub.3 0.8 to 1.20 ______________________________________
- and heating said mixture until a polymer having an x-ray powder diffraction pattern essentially that shown below, forms:
- ______________________________________ Interplanar Spacing Relative Intensity (in Angstroms) of the Lines ______________________________________ 11.20 Broad and blurred 4.30 Middle strong 3.43 Strong 3.29 Strong 3.08 Middle strong 2.97 Middle strong 2.71 Weak 2.46 Weak 2.30 Middle strong 2.11 Weak 1.92 Very strong 1.81 Middle strong ______________________________________
- combining said polymer with a substantial quantity of at least one filler to form a polymer/filler mixture;
- placing said polymer/filler mixture in a mold;
- and heating said polymer/filler mixture in said mold to form a solid, molded article.
The method of claim 11 wherein the polymer in said solid molded article is a composition expressed in terms of oxides as follows:
- 1.0.+-.0.2(yNa.sub.2 O,zK.sub.2 O):Al.sub.2 O.sub.3 :xSiO.sub.2
- where x is a value in the range of about 3.5 to about 4.5, and y and z have values up to 1 such that the sum of y and z equals 1.
Dependencies are inferred from the claim text.