GB2168362A - Compositions for packaging films - Google Patents
Compositions for packaging films Download PDFInfo
- Publication number
- GB2168362A GB2168362A GB08529717A GB8529717A GB2168362A GB 2168362 A GB2168362 A GB 2168362A GB 08529717 A GB08529717 A GB 08529717A GB 8529717 A GB8529717 A GB 8529717A GB 2168362 A GB2168362 A GB 2168362A
- Authority
- GB
- United Kingdom
- Prior art keywords
- butadiene
- styrene
- weight
- copolymer
- blend
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L9/00—Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
- C08L9/06—Copolymers with styrene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
- C08L25/02—Homopolymers or copolymers of hydrocarbons
- C08L25/04—Homopolymers or copolymers of styrene
- C08L25/06—Polystyrene
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L53/00—Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
- C08L53/02—Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers of vinyl-aromatic monomers and conjugated dienes
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
- C08L25/02—Homopolymers or copolymers of hydrocarbons
- C08L25/04—Homopolymers or copolymers of styrene
- C08L25/08—Copolymers of styrene
- C08L25/10—Copolymers of styrene with conjugated dienes
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Wrappers (AREA)
Abstract
A packaging film having high clarity and dead-fold properties, particularly for twist wrapping of goods such as confectionery, is formed from a blend comprising (1) 10 to 30% (preferably about 26%) by weight of a rubbery styrene/butadiene/styrene block copolymer having three or more blocks per molecule containing from 60 to 80% by weight of butadiene, (2) 70 to 90% by weight (preferably about 74%) of a styrene/butadiene copolymer (which may be block or random or partially both) containing from 25 to 35% by weight of butadiene, and (3) polystyrene in an amount based on the blend of from 1 to 60% by weight. The film is formed by extruding the mixture through a flat or circular die.
Description
SPECIFICATION
Dead - fold films
This invention is concerned with dead-fold films which have useful applications in the packaging of articles, such as confectionery, by the method of twist wrapping or by overwrapping and similar uses. A known film having twist-wrap applications comprises a composition consisting principally of polystyrene with the addition of a rubbery composition of a triblock copolymer of the styrene/butadiene/styrene (SBS) type, having a high content of butadiene. While such films have adequate dead fold properties in that there is substantially no tendency for the film to unwind after having been twist-wrapped around an article, there is an undesirable haze in the film which detracts from the presentation of the article for sale.
Such haze arises from the incompatibility of the polystyrene with the triblock copolymer.
It has now been found that the compatibility of the polystyrene with the triblock copolymer can be significantly improved by incorporating a selected styrene/butadiene copolymer into the blend thus providing a high clarity film having desirable dead-fold properties.
According to the present invention a packaging film having a combination of high clarity and dead fold properties comprises a blend of from 10 to 30% by weight of a styrene/butadiene/styrene block copolymer having three or more blocks per molecule and containing from 60 to 80% by weight of butadiene and of from 70 to 90% by weight of a styrene/butadiene copolymer containing from 25 to 35% by weight of butadiene and incorporated in the blend from 1 to 60% by weight, based on the blend, of polystyrene.
In a preferred form of the invention the styrene/butadiene/styrene copolymer is present in the blend from 25 to 28% by weight and preferably about 26%, and the styrene/butadiene copolymer is present in the blend from 72 to 75% by weight and more preferably about 74%.
The styrene/butadiene/styrene copolymer is of a thermoplastic rubbery composition which provides a desired level toughness to the film when present in an amount of at least 10% by weight of the blend.
The styrene/butadiene copolymer may be block, random or partially block partially random. In both copolymers it is important that there is substantially no cross-linking of the butadiene units.
The copolymer compositions are readily blended with the polystyrene and may, after being heated to a fluid state, by extruded into a film through a flat die or through a circular die to form a tube.
Haze in the film may be judged by eye or more accurately by instrument when the 'haze value' is expressed as the percentage of transmitted light which on passing through a sample of film deviates from the incident beam by forward scattering by more than an average of 2.5 to the incident beam. A haze value of 3.0 to 4.0% is considered to be fair and over 4.0% is unacceptable for average packaging purposes.
Dead-fold properties are determined by folding a sample of a film and noting whether there is any tendency to unfold. A film with good dead fold properties shows no significant tendency to unwind after being twisted upon itself, for example, when twisted around the end of an item of confectionery. The invention also includes a method of manufacture of a packaging film in accordance with the invention.
The invention will now be illustrated by way of the following Examples:
Examples
In four separate runs as shown in the accompanying Table various amounts of a rubbery styrene/butadiene/styrene (SBS) triblock copolymer containing 72% by weight of butadiene were blended with amounts of a partially block partially random styrene/butadiene copolymer containing 25% by weight of butadiene. Various amounts of polystyrene were added to the blend. The mixture was heated to a fluid state and extruded through a circular die to form a blown tubular film having a blow up ratio of 2 1/2.
The tubular film was air-cooled to a solid state, slit longitudinally to form a flat film and wound into a roll. In all cases the film exhibited desirable dead-fold properties.
In a fifth run, the conditions of the second run were repeated except that the styrene/butadiene/styrene triblock copolymer was replaced by a multiblock styrene/butadiene/styrene copolymer having significantly more than three blocks per molecule, containing 62% by weight of butadiene and marketed by the
Asahi Chemical Industry Company of Tokyo, Japan under the trade name 'TUFPRENE A'. The resulting film exhibited good dead-fold properties. The haze value in each case was measured and the results noted.
As shown in Table three further runs (6,7,8) were carried out in the absence of the styrene/butadiene copolymer and in each case an intense haze was found to be present.
TABLE
RUN BLEND % BY WEIGHT Polystyrene Haze Evaluation
% by weight Value
SBS SBS Styrene/ on blend
Tri- Multi- Butadiene
block block Copolymer
Copoly- Copoly
mer mer
1 20 - 80 30 2.3 GOOD
2 26 - 74 52.5 1.9 GOOD
3 30 - 70 30 3.1 FAIR
4 40 - 60 30 4.1 BAD
5 - 26 74 52.5 1.7 GOOD
6 100 - - 85 25.0 BAD
7 100 - - 90 19.0 BAD
8 - 100 - 70 6.4 BAD
It is to be understood that the present invention also includes the novel blends herein described.
Claims (10)
1. A packaging film having a combination of high clarity and dead fold properties comprising a blend of from 10 to 30% by weight of a styrene/butadiene/styrene block copolymer having three or more blocks per molecule and containing from 60 to 80% by weight of butadiene and from 70 to 90% by weight of a styrene/butadiene copolymer containing from 25 to 35% by weight of butadiene and incorporated in the blend from 1 to 60% by weight based on the blend of polystyrene.
2. A film as claimed in Claim 1 in which the styrene/butadiene/styrene copolymer is present in the blend in an amount from 25 to 28% by weight and the styrene/butadiene copolymer is present in an amount from 72 to 75% by weight.
3. A film as claimed in Claim 1 or Claim 2 in which the styrene/butadiene/styrene copolymer is present in the blend in an amount of about 26% by weight and the styrene/butadiene copolymer is present in an amount of about 74%.
4 A film as claimed in Claim 1, Claim 2 or Claim 3 in which the styrene/butadiene/styrene copolymer is a triblock copolymer.
5. A method of manufacture of a packaging film having a combination of high clarity and dead fold properties comprising blending together from 10 to 30% by weight of a styrene/butadiene/styrene block copolymer having three or more blocks per molecule and containing 60 to 80% by weight of butadiene and 70 to 90% by weight of a styrene/butadiene copolymer containing from 25 to 35% by weight of butadiene, incorporating in the blend from 1 to 60% by weight based on the blend of polystyrene and extruding the mixture in a fluid state through a die to form a film.
6. A method as claimed in Claim 5 in which the styrene/butadiene/styrene copolymer is a triblock copolymer.
7. A method as claimed in Claim 5 substantially as described in the Examples.
8. A film when produced by a method as claimed in Claims 5, 6 or 7.
9. A polymer blend comprising (a) a styrene/butadiene/styrene block coplymer having three or more blocks per molecule and containing from 60 to 80% by weight of butadiene, (b) a styrene/butadiene copolymer containing from 25 to 35% by weight of butadiene and (c) polystyrene, the amounts of components (a) and (b) being from 10 to 30% and from 70 to 90% by weight respectively, and the amount of component (c) being from 1 to 60% by weight based upon the total weight of components (a) and (b).
10. An article, including confectionery, wrapped with a film as claimed in any one of Claims 1 to 4 or 8, especially when wrapped by twist-wrapping.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB848431756A GB8431756D0 (en) | 1984-12-17 | 1984-12-17 | Dead-fold films |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8529717D0 GB8529717D0 (en) | 1986-01-08 |
| GB2168362A true GB2168362A (en) | 1986-06-18 |
| GB2168362B GB2168362B (en) | 1987-10-14 |
Family
ID=10571290
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB848431756A Pending GB8431756D0 (en) | 1984-12-17 | 1984-12-17 | Dead-fold films |
| GB08529717A Expired GB2168362B (en) | 1984-12-17 | 1985-12-03 | Compositions for packaging films |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB848431756A Pending GB8431756D0 (en) | 1984-12-17 | 1984-12-17 | Dead-fold films |
Country Status (1)
| Country | Link |
|---|---|
| GB (2) | GB8431756D0 (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2691436A1 (en) * | 1992-05-22 | 1993-11-26 | Martin Villarrubia Bernabe | Stretch cling film for food packaging - made by extrusion of a mixt. of a styrene]-butadiene]-styrene] copolymer and a sequenced styrene]-butadiene] copolymer |
| EP0810255A3 (en) * | 1996-05-30 | 1998-02-11 | Metallgesellschaft Aktiengesellschaft | Soluble polymeric film, process for its production and its use |
| US5969044A (en) * | 1996-05-30 | 1999-10-19 | Metallgesellschaft Aktiengesellschaft | Method of packaging air- and/or moisture-sensitive materials and for introducing the packaged materials into a reactor |
| RU2198791C2 (en) * | 2001-02-22 | 2003-02-20 | Общество с ограниченной ответственностью "Основание" | Method for manufacture of polystyrene film |
| WO2002022733A3 (en) * | 2000-09-15 | 2003-07-10 | Dow Global Technologies Inc | Styrenic polymer compositions with improved clarity |
| WO2005100471A3 (en) * | 2004-04-19 | 2006-01-05 | Nova Chem Int Sa | Thermoplastic elastomer resin composition |
| EP1702957A1 (en) * | 2005-03-14 | 2006-09-20 | Kraton Polymers Research B.V. | Hydrogenated block copolymer composition for overmoulding onto thermoplastics |
| WO2008083973A1 (en) * | 2007-01-12 | 2008-07-17 | Tarkett Sas | Composition and manufacturing process of a decorative surface covering |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2188832C2 (en) * | 2000-12-14 | 2002-09-10 | Открытое акционерное общество "УКРПЛАСТИК" | Polymeric film material production process |
-
1984
- 1984-12-17 GB GB848431756A patent/GB8431756D0/en active Pending
-
1985
- 1985-12-03 GB GB08529717A patent/GB2168362B/en not_active Expired
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2691436A1 (en) * | 1992-05-22 | 1993-11-26 | Martin Villarrubia Bernabe | Stretch cling film for food packaging - made by extrusion of a mixt. of a styrene]-butadiene]-styrene] copolymer and a sequenced styrene]-butadiene] copolymer |
| EP0810255A3 (en) * | 1996-05-30 | 1998-02-11 | Metallgesellschaft Aktiengesellschaft | Soluble polymeric film, process for its production and its use |
| US5969044A (en) * | 1996-05-30 | 1999-10-19 | Metallgesellschaft Aktiengesellschaft | Method of packaging air- and/or moisture-sensitive materials and for introducing the packaged materials into a reactor |
| WO2002022733A3 (en) * | 2000-09-15 | 2003-07-10 | Dow Global Technologies Inc | Styrenic polymer compositions with improved clarity |
| RU2198791C2 (en) * | 2001-02-22 | 2003-02-20 | Общество с ограниченной ответственностью "Основание" | Method for manufacture of polystyrene film |
| WO2005100471A3 (en) * | 2004-04-19 | 2006-01-05 | Nova Chem Int Sa | Thermoplastic elastomer resin composition |
| EP1702957A1 (en) * | 2005-03-14 | 2006-09-20 | Kraton Polymers Research B.V. | Hydrogenated block copolymer composition for overmoulding onto thermoplastics |
| WO2008083973A1 (en) * | 2007-01-12 | 2008-07-17 | Tarkett Sas | Composition and manufacturing process of a decorative surface covering |
| EP1953202A1 (en) * | 2007-01-12 | 2008-08-06 | Tarkett SAS | Composition and manufacturing process of a decorative surface covering |
| US8192846B2 (en) | 2007-01-12 | 2012-06-05 | Tarkett Sas | Composition and manufacturing process of a decorative surface covering |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8529717D0 (en) | 1986-01-08 |
| GB8431756D0 (en) | 1985-01-30 |
| GB2168362B (en) | 1987-10-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4311808A (en) | Cling film composition of olefin polymer blend | |
| CA2021119C (en) | Polymer base blend compositions containing destructurized starch | |
| US4430457A (en) | Cling/stretch wrap compositions | |
| AU740253B2 (en) | Improved antifog composition for polyolefin packaging films | |
| CA1197335A (en) | Stretch wrap cling polyethylene film | |
| EP0032804B1 (en) | Film-forming thermoplastic elastomeric polymer compositions | |
| GB2168362A (en) | Compositions for packaging films | |
| US4835194A (en) | Film-forming compositions and fog resistant film produced therefrom | |
| JPH05230304A (en) | Thermoplastic molding material and molded article produced therefrom | |
| US5326602A (en) | Polyethylene blends | |
| JPH0371465B2 (en) | ||
| KR100195776B1 (en) | Blow bottle made form polyolefin | |
| USRE30726E (en) | Polymer film having linear tear properties | |
| US3362839A (en) | Wax coating composition containing n-substituted fatty amides | |
| US4929681A (en) | Blends of LLDPE, polypropylene and aromatic polymers and high modulus films thereof | |
| CA1256230A (en) | Film blends of a polyethylene and polystyrene | |
| US5320899A (en) | Thermoplastic block copolymer films | |
| DE69806117T2 (en) | METHOD FOR PRODUCING A THERMOPLASTIC RESIN COMPOSITION AND MOLDED ARTICLE | |
| US4716201A (en) | Films of blends of linear ethylene polymers and aromatic polymers | |
| JPH07119044A (en) | Finishing agent composition for clothing | |
| JPS6341550A (en) | Resin composition for molding film | |
| US5726215A (en) | Styrene resin composition and shaped article thereof | |
| JP4823663B2 (en) | Stretch film for food packaging | |
| JPH05170940A (en) | Polystyrenic resin film | |
| EP0991716B1 (en) | Monolayer film |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 732E | Amendments to the register in respect of changes of name or changes affecting rights (sect. 32/1977) | ||
| PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19931203 |