Blockcopolymer compositions, having improved mechanical properties and processability and styrenic blockcopolymer to be used in them

Abstract

A composition to be used for the manufacture of fibers, filaments, melt blown or spun bond non-wovens or cast or blown films, comprising at least 50 wt % of a styrenic block copolymer; a polyolefin in an amount of from 10 to 30 wt %; a resin which is compatible with the poly(styrene) blocks in the styrenic block copolymer in an amount of at least 5 wt %, and a resin which is compatible with the hydrogenated polybutadiene blocks in the styrenic block copolymer an amount of at least 3 wt %, wherein all weight percentages are relative to the weight of the complete composition; styrenic block copolymers to be used therein; and fibers, melt blown or spun bond non-wovens or cast or blown films prepared from it.

1 - 10 . (canceled)  
     
     
         11 . A styrenic block copolymer, wherein the copolymer comprises: 
 i. a poly(styrene) content (PSC) of from 17 to 24 wt %;    ii. a molecular structure according to the general formula:     S−EB−S (1) or (S−EB) n X (2),    wherein each S independently is a polymer block of styrene and EB is a hydrogenated polymer block of butadiene, n is an integer equal to or greater than 2, and X is the residue of a coupling agent;    iii. an apparent molecular weight of the poly(styrene) blocks (S) in the range of from 6,000 to 9,000;    iv. an apparent molecular weight of the complete styrenic block copolymer in the range of from 80,000 to 150,000;    V. a 1,2-addition degree (vinyl content) in a precursor poly (butadiene) block (EB) precursor in the range of from 60 to 80 (mole/mole);    vi. the block EB has a hydrogenation degree of at least 80%, and    vii. an optional diblock S−EB content of at most 20 mole %, relative to the total block copolymer amount.    
     
     
         12 . The styrenic block copolymer of  claim 11 , wherein the apparent molecular weight of the poly(styrene) blocks (S) in the range of from 7,000 to 8,500.  
     
     
         13 . The styreneic block copolymerof  claim 11 , wherein the hydrogenation degree of the EB block is at least 90%.  
     
     
         14 . The styrenic block copolymer of  claim 11 , wherein the hydrogenation degree of the EB block is at least 95%.  
     
     
         15 . The styrenic block copolymer of  claim 14 , wherein the 1,2-addition degree in the EB block is in the range of from 65 to 75%.  
     
     
         16 . The styrenic block copolymer of  claim 11 , wherein the apparent molecular weight of the styrenic block copolymer is in the range from 100,000 to 120,000.  
     
     
         17 . The styrenic block copolymer of  claim 13 , wherein the apparent molecular weight of the styrenic block copolymer is in the range from 100,000 to 120,000.  
     
     
         18 . The styrenic block copolymer of  claim 14 , wherein the apparent molecular weight of the styrenic block copolymer is in the range from 100,000 to 120,000.