# US 2016/0355674 A1 · High impact polystyrene having high modulus and resistance to environmental stress cracking > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0355674 A1 - Document ID: US20160355674A1 - Status: Published application - Kind: A1 - Application number: 15/241,142 - Filed: 2016-08-19 - Published: 2016-12-08 - Earliest claimed: 2015-08-21 - Assignees: Trinseo Europe GmbH - Applicants: Trinseo Europe GmbH - Inventors: Rudi Veraart; Gilbert Bouquet; Mark Georges Vreys; Ronald Van Daele; Alexander De Bokx - Web page: https://patentgrep.com/patent/US20160355674A1 ## CPC - C08L 25/06: Polystyrene - C08F 279/02: on to polymers of conjugated dienes - C08L 51/04: grafted on to rubbers - C08L 2205/06: having improved processability or containing aids for moulding methods - C08L 2205/22: Mixtures comprising a continuous polymer matrix in which are dispersed crosslinked particles of another polymer - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS ## Abstract High impact polystyrenes and related monovinyl aromatic polymers generally have either a high modulus or good resistance to environmental stress cracking. The present invention is directed at polymeric materials having both a high modulus and good resistance to environmental stress cracking thus enabling the down gauging of parts, and or the use of the materials in new applications. The invention is predicated on the use of one or more, or even all of the following features: a high molecular weight matrix polymer, reduced concentration of elastomeric polymer, or methods that result in large rubber particle size. ## Claims ### Claim at position 1 1-21: (canceled) ### Claim 22 A composition comprising: a rubber-modified monovinyl aromatic polymer i) including about 90 weight percent or more of a monovinyl aromatic polymer matrix, based on the total weight of the rubber-modified monovinyl aromatic polymer; and ii) from about 2 to about 7.5 weight percent of one or more elastomeric polymers, based on the total weight of the composition; and having a volume average diameter of 5 μm to 30 μm; and greater than 2 weight percent to 7 weight percent mineral oil, based on the total weight of the compositions; wherein the monovinyl aromatic polymer matrix is derived from one or more monovinyl aromatic monomers, and the monovinyl aromatic polymer matrix has a sufficiently high molecular weight so that the retention in the elongation at break after 10 days in corn oil at 1% strain is about 15% or more; the monovinyl aromatic polymer matrix is sufficiently rigid so that the composition has a tensile modulus of about 1500 MPa or more as measured according to ISO 527-2; and the molecular weight of the monovinyl aromatic polymer matrix is characterized by a weight average molecular weight of 200,000 to about 280,000 g/mol and a polydispersity index of 2.7 or more. ### Claim 23 (depends on 22) The composition of claim 22, wherein the elastomeric polymer has an average diameter from 6 μm to 15 μm, and the elastomeric polymer includes at least 75 weight percent butadiene monomer based on the total weight of the elastomeric polymer. ### Claim 24 (depends on 22) The composition of claim 22, wherein the monovinyl aromatic polymer matrix has a weight average molecular weight of 205,000 g/mol or more, and includes about 95 weight percent to about 100 weight percent styrene, based on the total weight of the monvinyl aromatic polymer matrix. ### Claim 25 (depends on 24) The composition of claim 24, wherein the elastomeric polymer is present as grafted and cross-linked rubber particles dispersed within the monovinyl aromatic polymer matrix. ### Claim 26 (depends on 25) The composition of claim 25, wherein the monovinyl aromatic polymer matrix consists essential of styrene, and is sufficiently rigid and the concentration of the elastomeric polymer is sufficiently low so that the tensile modulus of the composition is about 1600 MPa or more. ### Claim 27 (depends on 26) The composition of claim 26, wherein the one or more elastomeric polymers are present in an amount from about 3 to about 7.1 weight percent, based on the total weight of the composition. ### Claim 28 (depends on 27) The composition of claim 27, wherein the rubber-modified monovinyl aromatic polymer is a reactor blend having the one or more monovinyl aromatic monomers polymerized in the presence of the one or more elastomeric polymers. ### Claim 29 (depends on 28) The composition of claim 28, wherein the molecular weight distribution of the monovinyl aromatic polymer is characterized by a polydispersity index of 3.0 to 8. ### Claim 30 (depends on 29) The composition of claim 29, wherein the monovinyl aromatic polymer is characterized by a z-average molecular weight of about 360,000 g/mol or more. ### Claim 31 (depends on 30) The composition of claim 30, wherein the concentration of the elastomeric polymer is about 4 weight percent or more based on the total weight of the composition, and wherein, and the elastomeric polymer has an average diameter from 6 μm to 15 μm. ### Claim 32 (depends on 31) The composition of claim 31, wherein the composition consists of the monovinyl aromatic polymer, the elastomeric polymer and the mineral oil. ### Claim 33 A composition consisting of: a rubber-modified monovinyl aromatic polymer consisting of i) about 90 weight percent or more of a monovinyl aromatic polymer matrix, based on the total weight of the rubber-modified monovinyl aromatic polymer; and ii) from about 2 to about 7.5 weight percent of one or more elastomeric polymers, based on the total weight of the composition; and having a volume average diameter of 5 μm to 30 μm; and greater than 2 weight percent to 7 weight percent mineral oil, based on the total weight of the compositions; wherein the monovinyl aromatic polymer matrix is derived from one or more monovinyl aromatic monomers, and the monovinyl aromatic polymer matrix has a sufficiently high molecular weight so that the retention in the elongation at break after 10 days in corn oil at 1% strain is about 15% or more; the monovinyl aromatic polymer matrix is sufficiently rigid so that the composition has a flexural modulus of about 1500 MPa or more as measured according to ISO 178; and the molecular weight of the monovinyl aromatic polymer matrix is characterized by a weight average molecular weight of 200,000 to about 280,000 g/mol and a polydispersity index of 2.7 or more. ### Claim 34 (depends on 22) The composition of claim 22, wherein the monovinyl aromatic polymer is characterized by a weight average molecular weight of 205,000 g/mol or more; the molecular weight distribution of the monovinyl aromatic polymer is characterized by a polydispersity index of 3.0 or more; the monovinyl aromatic polymer includes about 95 weight percent or more styrene, based on the total weight of the monovinyl aromatic polymer; the concentration of the elastomeric polymer is sufficiently low so that the tensile modulus of the composition is about 1700 MPa or more; the monovinyl aromatic polymer is characterized by a z-average molecular weight of about 360,000 g/mol or more; the concentration of the elastomeric polymer is 7.1 weight percent or less, based on the total weight of the composition. the concentration of the elastomeric polymer is about 4 weight percent or more based on the total weight of the composition; and the elastomeric polymer includes at least 75 weight percent butadiene monomer based on the total weight of the elastomeric polymer. ### Claim 35 (depends on 34) The composition claim 34, wherein the elastomeric polymer has an average diameter from 6 μm to 15 μm. ### Claim 36 (depends on 34) A refrigerator liner including a composition of claim 34. ### Claim 37 (depends on 36) The refrigerator liner of claim 36, wherein the refrigerator liner is characterized by ESCR performance determined by retention in elongation at break after 10 days in corn oil at 1% strain of about 15% or more. ### Claim 38 A process including a step of extruding and/or therm ### Claim 39 A method of forming a composition comprising the steps of: i) polymerizing one or more monovinyl aromatic monomers in the presence of one or more elastomeric polymers to form a rubber-modified monovinyl aromatic polymer including a monovinyl aromatic polymer matrix characterized by a weight average molecular weight of 200,000 to about 280,000 g/mol and a polydispersity index of 2.7 or more; and ii) preparing a polymeric composition by blending at least the rubber-modified monovinyl aromatic polymers and 2 weight percent to 7 weight percent of mineral oil; wherein the the rubber-modified monovinyl aromatic polymer includes: i) about 90 weight percent or more of the monovinyl aromatic polymer matrix, based on the total weight of the polymeric composition; and ii) from about 2 to about 7.5 weight percent of the one or more elastomeric polymers, based on the total weight of the rubber-modified monovinyl aromatic polymer; wherein the one or more elastomeric polymers has a volume average diameter of 5 μm to 30 μm; the monovinyl aromatic polymer matrix has a sufficiently high molecular weight so that the retention in the elongation at break after 10 days in corn oil at 1% strain is about 15% or more; and the monovinyl aromatic polymer matrix is sufficiently rigid so that the composition has a tensile modulus of about 1500 MPa or more as measured according to 527-2. ### Claim 40 (depends on 39) The process of claim 39, wherein the elastomeric polymer has an average diameter from 6 μm to 15 μm. ### Claim 41 (depends on 40) The method of claim 40, wherein the monovinyl aromatic polymer matrix includes 95 weight percent or more styrene, based on the total weight of the monovinyl aromatic polymer matrix.