Blow molding polystyrene nanocomposites

Abstract

Disclosed is a polystyrene based polymer/layered compound nanocomposite for injection blow molding or injection stretch blow molding of articles. The nanocomposite can reduce shrinkage and warpage to the preform during the reheating process compared to neat polystyrene. The incorporation of layered compounds can increase the processability of PS preforms, help improve heating efficiency, and improve bottle mechanical properties. The layered compound can be treated with chemicals or compounds having an affinity with the styrene monomer or polystyrene, thus producing a treated layered compound having an affinity with the styrene monomer or polystyrene. The monomer and the layered compound can be combined prior to polymerization. The polymer and layered compound can be combined by solution mixing in a solvent. The layered compound can also be incorporated into the mixture by compounding a polymer product with the layered compound, or the combination of any of the above three approaches

1 - 13 . (canceled) 
     
     
         14 . A method of forming a blow molded article comprising:
 providing a nanocomposite comprising a polystyrene based polymer and a layered compound;   wherein the layered compound is treated with an organic compound to thereby form a material having an affinity with styrene, wherein the organic compound comprises a ring structured group or a methacrylate group selected from the group consisting of butyl methacrylate, cyclohexane, methyl styrene, cyclopentane, chlorotoluene, methyl methacrylate, xylene, toluene, vinyl toluene, benzene, methylcyclohexanone, styrene, furan, chlorobenzene, cyclohexanone, dichlorobenzene, nitrobenzene, iodobenzene, cyclopentanone, cyclobutanedione, and combinations thereof;   forming a preform having at least one layer made from the nanocomposite;   heating the preform; and   injection blow molding the preform into an article.   
     
     
         15 . The method of  claim 14 , wherein the injection blow molding comprises injection stretch blow molding the preform into the article. 
     
     
         16 . The method of  claim 14 , wherein the layered compound comprises natural clay, synthetic clay, sols, colloids, gels, or fumes. 
     
     
         17 . (canceled) 
     
     
         18 . The method of  claim 14 , wherein a difference between a solubility parameter of the ring structured group or the methacrylate group and a solubility parameter of styrene is no more than 3.0 (MPa 1/2 ). 
     
     
         19 - 21 . (canceled) 
     
     
         22 . The method of  claim 14 , wherein the heating of the preform results in a shrinkage of less than 40% and a warpage of less than 8%. 
     
     
         23 . The method of  claim 14 , wherein the layered compound improves the preform heating efficiency and the preform reaches a temperature at least 5° F. higher than an identical preform without the layered compound when heated under the same conditions. 
     
     
         24 . The method of  claim 14 , wherein the preform includes at least one layer of the nanocomposite and at least one layer of polystyrene based polymer that is not a nanocomposite. 
     
     
         25 . An article formed by the method of  claim 14 . 
     
     
         26 . A method for production of a blow molded article having improved morphology, processability, heating efficiency, and article properties comprising:
 mixing polystyrene based polymer with a treated layered compound to form a polymeric nanocomposite;   forming a preform having at least one layer made from the polymeric nanocomposite;   heating the preform to a first temperature sufficient for blow molding the preform;   injection stretch blow molding the preform into an article;   wherein the treated layered compound has been formed by treating a layered compound with an organic compound to produce the treated layered compound having an affinity with the polystyrene based polymer prior to mixing;   wherein the organic compound comprises a ring structured group or a methacrylate group selected from the group consisting of butyl methacrylate, cyclohexane, methyl styrene, cyclopentane, chlorotoluene, methyl methacrylate, xylene, toluene, vinyl toluene, benzene, methylcyclohexanone, styrene, furan, chlorobenzene, cyclohexanone, dichlorobenzene, nitrobenzene, iodobenzene, cyclopentanone, cyclobutanedione, and combinations thereof;   wherein the layered compound improves the preform heating efficiency and the first temperature is at least 5° F. higher than the temperature of an identical preform without the layered compound when heated under the same conditions;   wherein the heating of the preform results in a shrinkage of less than 40% and a warpage of less than 8%.   
     
     
         27 . The method of  claim 26 , wherein the mixing comprises at least one of the processes of:
 compounding the polystyrene based polymer and the treated layered compound;   solution mixing the polystyrene based polymer and the treated layered compound in a solvent; or   mixing the treated layered compound with a styrene based monomer prior to polymerization.   
     
     
         28 . The method of  claim 14 , wherein the organic compound comprises a ring structured group or a methacrylate group selected from the group consisting of: butyl methacrylate, cyclohexane, methyl styrene, cyclopentane, chlorotoluene, xylene, toluene, vinyl toluene, benzene, methylcyclohexanone, styrene, furan, chlorobenzene, cyclohexanone, dichlorobenzene, nitrobenzene, iodobenzene, cyclopentanone, cyclobutanedione, and combinations thereof. 
     
     
         29 . The method of  claim 14 , wherein the organic compound comprises a ring structured group or a methacrylate group selected from the group consisting of: cyclohexane, methyl styrene, cyclopentane, chlorotoluene, methyl methacrylate, xylene, toluene, vinyl toluene, benzene, methylcyclohexanone, styrene, furan, chlorobenzene, cyclohexanone, dichlorobenzene, nitrobenzene, iodobenzene, cyclopentanone, cyclobutanedione, and combinations thereof. 
     
     
         30 . The method of  claim 14 , wherein the organic compound comprises a ring structured group or a methacrylate group selected from the group consisting of: cyclohexane, methyl styrene, cyclopentane, chlorotoluene, xylene, toluene, vinyl toluene, benzene, methylcyclohexanone, styrene, furan, chlorobenzene, cyclohexanone, dichlorobenzene, nitrobenzene, iodobenzene, cyclopentanone, cyclobutanedione, and combinations thereof. 
     
     
         31 . The method of  claim 14 , wherein the layered compound comprises an organoclay. 
     
     
         32 . The method of  claim 14 , wherein the polystyrene based polymer comprises a homopolymer or a styrenic polymer with one or more comonomers, and wherein the polystyrene based polymer is present in the nanocomposite in an amount of from 90 wt. % to 99.5 wt. % based on the total weight of the nanocomposite. 
     
     
         33 . The method of  claim 14 , wherein the polystyrene based polymer further comprises an elastomeric phase that is embedded in a polymer matrix, wherein the elastomeric phase is selected from one or more of a conjugated diene monomer, an aliphatic conjugated diene monomer, and blends or copolymers of the diene monomers, and wherein the elastomeric phase is present in the polystyrene based polymer in an amount ranging from 0.1 wt. % to 10 wt. %. 
     
     
         34 . The method of  claim 14 , wherein the injection blow molding of the preform into the article comprises a co-injection blow molding process. 
     
     
         35 . The method of  claim 14 , wherein the injection blow molding of the preform into the article comprises a single or double stage injection blow molding process. 
     
     
         36 . A preform useful in blow molding processes comprising:
 a nanocomposite comprising a polystyrene based polymer and a layered compound;   wherein the layered compound is treated with an organic compound to thereby form a material having an affinity with styrene; and   wherein the organic compound comprises a ring structured group or a methacrylate group selected from the group consisting of butyl methacrylate, cyclohexane, methyl styrene, cyclopentane, chlorotoluene, methyl methacrylate, xylene, toluene, vinyl toluene, benzene, methylcyclohexanone, styrene, furan, chlorobenzene, cyclohexanone, dichlorobenzene, nitrobenzene, iodobenzene, cyclopentanone, cyclobutanedione, and combinations thereof.