Low free 2-mercaptoethanol ester and uses thereof

Abstract

A novel Low Free 2-MercaptoEthanol Ester has been used to prepare Alkyl Tin Reverse Ester Stabilizers as well as used to enhance the thermal performance of those Alkyl Tin Reverse Ester Stabilizers or Alkyl Tin Thioglycolate Stabilizers or Alkyl Tin Mercaptides for PVC applications where odor during PVC compounding, processing, or of the final PVC article has prevented widespread use of Alkyl Tin Reverse Ester Stabilizers.

1 . A Low Free 2-MercaptoEthanol Ester (LFMEE) that is obtained through removal of 2-MercaptoethylEthanol from a standard 2-MercaptoEthanol Ester, wherein the resulting LFMEE have residual 2-Mercaptoethanol below 1.0 wt %. 
     
     
         2 . The LFMEE of  claim 1  wherein the resulting LFMEE have residual 2-Mercaptoethanol below 0.7 wt %. 
     
     
         3 . The LFMEE of  claim 1  wherein the resulting LFMEE have residual 2-Mercaptoethanol below 0.5 wt %. 
     
     
         4 . A method of using the LFMEE of  claim 1  to enhance thermal performance of alkyl tin thioglycolate ester stabilizers. 
     
     
         5 . A method of using the LFMEE of  claim 1  to enhance thermal performance of alkyl tin reverse ester stabilizers. 
     
     
         6 . A method of using the LFMEE of  claim 1  to enhance thermal performance of alkyl tin mercaptide stabilizers. 
     
     
         7 . The method of  claim 6  wherein the mercaptide can be dodocylmercaptan or carboxylates. 
     
     
         8 . The method of  claim 7  wherein the mercaptide is Maleates. 
     
     
         9 . The method of  claim 6  wherein the stabilizer further includes sulfide bridging for alkyl groups ranging of C1-C8. 
     
     
         10 . The method of  claim 6  wherein the alkyl tin mercaptide stabilizer has alkyl tin groups having both mono and di components, wherein the mono and di components of alkyl tin groups are in ratios ranging from 100% di to 100% mono and all combinations between. 
     
     
         11 . The method of  claim 6  wherein the amount of LFMEE used in the stabilizer can range from 5 wt % to 75 wt %. 
     
     
         12 . The method of  claim 6  wherein the amount of LFMEE used in the stabilizer can range from 10 wt % to 40 wt %. 
     
     
         13 . The method of  claim 4  wherein the stabilizer further includes Ca/Zn-based boosters, organic-based stabilizers and/or other traditional performance boosters such as BHT, polyols, metallic salts or other co-stabilizers. 
     
     
         14 . A composition comprising:
 (a) an alkyl tin reverse ester stabilizer; and   (b) a Low Free 2-MercaptoEthanol Ester (LFMEE) that is obtained through removal of 2-MercaptoethylEthanol from a standard 2-MercaptoEthanol Ester, wherein the resulting LFMEE have residual 2-Mercaptoethanol below 1.0 wt %;   
       wherein the ratio of alkyl tin reverse ester stabilizer:LFMEE ranges from 95 wt %:5 wt % to 25 wt %:75 wt %. 
     
     
         15 . The composition of  claim 14  wherein the ratio of alkyl tin reverse ester stabilizer:LFMEE ranges from 85 wt %:15 wt % to 60 wt %:40 wt %. 
     
     
         16 . A method of using the LFMEE of  claim 1  as a ligand with 2-EHMA, carboxylates, lauryl mercaptan, 2-Mercaptothanol, thioglycolic acid, alkoxides or sulfide. 
     
     
         17 . The method of  claim 16  wherein the LFMEE is used along with other ligands in combinations with 2-EHMA, carboxylates, lauryl mercaptan, 2-Mercaptothanol, thioglycolic acid, alkoxides or sulfide. 
     
     
         18 . A method of preparing a PVC stabilizer, the method comprising:
 (a) reacting 1.02 eq of a Low Free 2-MercaptoEthanol Ester (LFMEE) and Disodium Sulfide with a mixture of Monooctyl Tin Trichloride (95 wt %) and Dioctyl Tin Dichloride (5 wt %) representing 1.0 equivalents of chloride using aqueous Sodium Hydroxide aqueous solution, wherein the LFMEE is obtained through removal of 2-MercaptoethylEthanol from a standard 2-MercaptoEthanol Ester, wherein the resulting LFMEE have residual 2-Mercaptoethanol below 1.0 wt %;   (b) allowing the mixture to settle;   (c) removing the bottom aqueous layer;   (d) drying the remaining organic phase; and   (e) filtering the dried organic phase.   
     
     
         19 . The method of  claim 18  wherein the drying step (d) is done under vacuum. 
     
     
         20 . The method of  claim 18  wherein the drying step (d) is done under heat. 
     
     
         21 . The method of  claim 18  wherein the drying step (d) is done under vacuum and heat. 
     
     
         22 . The method of  claim 18  wherein step (e) is carried out until it yields a clear liquid. 
     
     
         23 . (canceled)