Thermoplastic elastomer compositions having biorenewable content

Abstract

Thermoplastic elastomer compositions, in particular derived from one or more styrenic block copolymers, a plurality of biorenewable materials, preferably a softener and one or more synergistic additives such as a polar polymer; a synergistic block copolymer such as a relatively high molecular weight styrenic block copolymer; and/or filler. In one preferred embodiment, the styrenic block copolymer comprises a controlled distribution copolymer block including a conjugated diene and a mono alkenyl arene. Numerous desirable articles can be formed from the compositions. Processes for preparing the compositions and articles are disclosed.

1 . A thermoplastic elastomer composition, comprising:
 a styrenic block copolymer;   a biorenewable softener comprising one or more of a natural ester; a natural, fatty ether; a natural, fatty alcohol; and a natural, fatty amine in an amount from 1 to 90 parts by weight; and   at least one synergistic additive comprising one or more of thermoplastic starch, a biorenewable polar polymer, and a high molecular weight styrenic block copolymer, wherein all said parts are based on 100 parts by weight of the composition.   
     
     
         2 . The composition according to  claim 1 , wherein the styrenic block copolymer is present in an amount from 1 to 90 parts by weight, wherein the natural ester is present and is an ester-containing oil which is present in an amount from 1 to 85 parts by weight, and wherein the composition further includes a polyolefin. 
     
     
         3 . The composition according to  claim 2 , wherein the composition includes the thermoplastic starch in an amount from 2 parts to 80 parts by weight. 
     
     
         4 . The composition according to  claim 3 , wherein the composition further includes a functionalized styrenic block copolymer. 
     
     
         5 . The composition according to  claim 4 , wherein a dispersion aid is present in an amount from 1 to 80 parts by weight per 100 parts by weight of the thermoplastic starch. 
     
     
         6 . The composition according to  claim 5 , wherein the dispersion aid comprises glycerin, and wherein the functionalized styrenic block copolymer comprises a maleic anhydride functionalized styrenic block copolymer. 
     
     
         7 . The composition according to  claim 3 , wherein the thermoplastic starch is present in an amount from 2 to 40 parts by weight, wherein the styrenic block copolymer is present in an amount from 1 to 30 parts by weight, wherein the biorenewable softener is present in an amount from 5 to 75 parts by weight. 
     
     
         8 . The composition according to  claim 1 , wherein the biorenwable polar polymer is present in an amount from about 2 to about 60 parts by weight, and wherein the composition is free of mineral oil. 
     
     
         9 . The composition according to  claim 1 , wherein the biorenewable polar polymer is present in an amount from 1 to 80 parts by weight, wherein the natural ester is present and is an ester-containing oil in an amount from 1 to 85 parts by weight, wherein the styrenic block copolymer is present in an amount from 1 to 45 parts by weight. 
     
     
         10 . The composition according to  claim 9 , wherein the biorenewable polar polymer is one or more of a polylactic acid, polylactide, poly(glycolic acid), polyglycolide, poly(lactic-co-glycolic), poly(lactide-co-glycolide), polyglyconate, poly(hydroxyalkanoate), polyorthoester, polycaprolactone, polydioxanone, polyanhydride, and polyether-block-amide. 
     
     
         11 . The composition according to  claim 10 , wherein the biorenewable polar polymer is present in an amount from about 2 parts to about 60 parts by weight, wherein the ester-containing oil is present in an amount from about 10 parts to about 65 parts by weight, and wherein the composition is free of a mineral oil. 
     
     
         12 . The composition according to  claim 2 , wherein the ester-containing oil comprises hydrogenated oil. 
     
     
         13 . The composition according to  claim 9 , wherein the composition further includes a polyolefin in an amount from 0.5 to 60 parts by weight. 
     
     
         14 . The composition according to  claim 1 , wherein the natural, fatty amine is present. 
     
     
         15 . The composition according to  claim 14 , wherein the composition further includes a functionalized styrenic block copolymer and a polyolefin. 
     
     
         16 . The composition according to  claim 1 , wherein the composition comprises the natural, fatty amine, and wherein a polyolefin is present in an amount from 0.5 to 60 parts by weight. 
     
     
         17 . The composition according to  claim 1 , wherein the styrenic block copolymer comprises at least one controlled distribution copolymer block having a conjugated diene and a mono alkenyl arene in an amount from 5 to 90 parts by weight. 
     
     
         18 . The composition according to  claim 11 , wherein the styrenic block copolymer comprises at least one controlled distribution copolymer block having a conjugated diene and a mono alkenyl arene in an amount from 5 to 90 parts by weight. 
     
     
         19 . An article comprising the composition according to  claim 1 . 
     
     
         20 . A process for preparing a thermoplastic elastomer composition, comprising the step of combining the components set forth in  claim 1 , utilizing a one step compounding process.