Classifications

• • 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
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F297/00—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer
  • C08F297/02—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type
  • C08F297/04—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type polymerising vinyl aromatic monomers and conjugated dienes
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F297/00—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer
  • C08F297/02—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type
  • C08F297/04—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type polymerising vinyl aromatic monomers and conjugated dienes
  • C08F297/044—Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer using a catalyst of the anionic type polymerising vinyl aromatic monomers and conjugated dienes using a coupling agent
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J153/00—Adhesives based on block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Adhesives based on derivatives of such polymers
  • C09J153/02—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
  • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
  • C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials

Definitions

• the present invention comprises a poly (styrene-butadiene-styrene) polymer having a high vinyl content in the butadiene block for packaging tape adhesives and a hot melt polymer adhesive composition comprising said poly (styrene-butadiene-styrene) polymers (SBS).
• SBS poly (styrene-butadiene-styrene) polymers
• the present invention concerns a hot melt adhesive composition having equal or better properties compared to emulsion acrylic tapes.
• the adhesive composition of the present invention has excellent tack, adhesive strength, creep resistance and also an excellent treatment capability at high temperature and high box closing properties.
• the adhesives of the present invention are suitable for adhesion tapes, labels, pressure sensitive sheets, tacky adhesives for fixing carpets etc.
• the advantages of the adhesives of the present invention are that they are lower in cost compared to emulsion acrylic based adhesives or poly (styrene-isoprene- styrene) based adhesives (SIS) while having comparable or better properties.
• Hot melt adhesives are known, for instance, in the JP 2001787 describing tacky adhesive compositions for tapes comprising a block copolymer of a vinylaromatic hydrocarbon and a high vinyl polybutadiene block.
• the composition comprises a block copolymer, a tackifying resin and at least one phenol compound.
• the block copolymer is composed of at least one polymeric block mainly containing butadiene. It has a vinylaromatic hydrocarbon content of 10-36% by weight and the butadiene portions have a vinyl content of 15-55%.
• the JP 63182386 discloses sticky block copolymer compositions containing a vinyl aromatic-butadiene block copolymer, a tackifying resin and a phenolic compound.
• the block copolymer is mainly composed of vinyl aromatic hydrocarbon and at least one polymer block composed of polybutadiene .
• the EP-A-0 243 956 discloses an adhesive composition comprising a block copolymer containing at least one vinylaromatic hydrocarbon block and one butadiene containing block, wherein the relationship between the vinylaromatic hydrocarbon block and the 1,2 -vinyl content in the butadiene portion is within a ratio between 40 and 70.
• the polymers that have been used have a melt flow rate of 5 g/10 min (200°C, 5 kg) .
• hot melt compositions however do not have the same properties as those based on SIS in respect of the tack, adhesive strength creep resistance and treatment capacity at high temperature as well as high box closing properties .
• the object of the invention is a hot melt adhesive composition having equal or better properties compared to prior art adhesives, especially the acrylic emulsion based adhesives while being cheaper than poly (styrene-isoprene- styrene) (SIS) based adhesives.
• SIS poly (styrene-isoprene- styrene)
• Poly (styrene-isoprene-styrene) polymers are currently rarely used in pressure sensitive adhesives despite their relative low cost. The main reason for this is their high viscosity and tendency to cross-link so that the processing step becomes a limiting factor. Surprisingly a new SBS polymer has been developed with molecular parameters suitable for to hot melt adhesive applications.
• a poly (styrene-butadiene-styrene) polymer having a high vinyl content in the butadiene block comprising in combination : i) a polystyrene content (PSC) within a range of 15-20% by weight , ii) a coupling efficiency of 50-80%, iii) a step I molecular weight (MW) between 9,000 and 10,000 kg/mol iv) a vinyl content between about 20-45% by weight.
• PSC polystyrene content
• MW molecular weight
• a hot melt adhesive composition comprising: a) a poly (styrene-butadiene-styrene) polymer having a high vinyl content in the butadiene block b) a tackifying resin c) a plasticizer d) an anti-oxidant wherein said polymer has : i) a polystyrene content (PSC) within a range of 15-20% by weight, ii) a coupling efficiency (CE) of 50-80%, iii) a step I molecular weight (MW) between 9,000 and
• Preferred poly (styrene-butadiene-styrene) polymers having a high vinyl content in the butadiene block have a polystyrene content between 16-19% by weight, more preferably 16-18%. Likewise the preferred polymers have a coupling efficiency between 60-75%, more preferably 65- 70%. Moreover the preferred polymers have a vinyl content between 25-40% by weight, more preferably 30-35.
• a suitable embodiment of the present invention is defined as follows: PSC content (%) 16
• Step I MW (kg/mol) 9,100
• the polymer is defined as follows: PSC content (%) 18
• Step I MW (kg/mol) 9,100
• Suitable styrenes useful for preparing the polystyrene blocks of the SBS of the present invention are for example styrene, o-methylstyrene, p-methylstyrene, m- methylstyrene, p-tert-butylstyrene, dimethylstyrene, and various other alkyl-substituted styrenes, alkoxy- substituted styrenes vinylnaphthalene and vinyl xylene.
• the alkyl and alkoxy groups of the alkyl -substituted or alkoxy-substituted styrenes respectively preferably contain from 1 to 6 carbon atoms, preferably from 1 to 4 carbon atoms. It is to be noticed that this list is merely illustrative and should not have a limiting effect.
• the polystyrene blocks may comprise minor amounts (e.g. up to 5% by weight) of copolymerizable monomers.
• any suitable difunctional coupling agent can be used.
• the same polymer may be produced by what is called “full sequential”. This is also within the scope of this invention.
• the coupling agent may (not preferred) be a multifunctional coupling agent. Suitable coupling agents are dibromo ethane diglycidyl ether of bisphenol A and such like components as known in the art.
• Suitable tackifiers for preparing the hot melt adhesive composition of the present invention are well- known in the art. They may for example, be selected from the group consisting of compatible C5 hydrocarbon resins, hydrogenated C5 hydrocarbon resins, styrenated C5 resins,
• C5/C9 resins C5/C9 resins, styrenated terpene resins, fully hydrogenated or partially hydrogenated C9 hydrocarbon resins, rosins esters, rosins derivatives and mixtures thereof .
• composition according to the present invention preferably comprises from 50 to 200 parts by weight, more preferably from 100 to 150 parts by weight of a tackifier.
• the preferred tackifying resins useful in the present invention are selected within the group of HERCOTAC 205 (trademark) , an aromatic modified hydrocarbon resin of the Hercules grade range, used for natural rubber based packaging tapes; PICCOTAC 212 (trademark) a purely aliphatic resin widely used in hot melt pressure sensitive adhesives; MBG 223, a Hercules development grade which is a 35% aromatic modified C 5 resin, developed for tackifying SBS based adhesives; MBG 264, a partially hydrogenated hydrocarbon resin used in radiation curable adhesives based on SBS; and A 2514 which is a liquid developmental resin, with a very low softening point to be used in combination with a solid resin to increase the tack properties .
• Suitable plasticizers for use in preparing the hot melt adhesive compositions of the present invention include plasticizing oils like low aromatic content hydrocarbon oils that are paraffinic or naphthenic in character (carbon aromatic distribution £5%, preferably 2%, more preferably 0% as determined according to DIN 51378) .
• plasticizing oils like low aromatic content hydrocarbon oils that are paraffinic or naphthenic in character (carbon aromatic distribution £5%, preferably 2%, more preferably 0% as determined according to DIN 51378) .
• Those products are commercially available from the Royal Dutch/Shell Group of companies, like SHELLFLEX, CATENEX, and ONDINA oils.
• Other oils include KAYDOL oil from Witco, or TUFFLO oils from Arco.
• plasticizers include compatible liquid tackifying resins like REGALREZ R-1018. (SHELLFLEX, CATENEX, ONDINA, KAYDOL, TUFFLO and REGALREZ are trademarks) .
• plasticizers might also be added, like olefin oligomers; low molecular weight polymers ( ⁇ 30,000 g/mol) like liquid polybutene or liquid polyisoprene copolymers, like liquid styrene/isoprene copolymers or hydrogenated styrene/isoprene copolymers and liquid alpha-olefin polymers; vegetable oils and their derivatives; or paraffin and microcrystalline waxes.
• olefin oligomers low molecular weight polymers ( ⁇ 30,000 g/mol) like liquid polybutene or liquid polyisoprene copolymers, like liquid styrene/isoprene copolymers or hydrogenated styrene/isoprene copolymers and liquid alpha-olefin polymers
• vegetable oils and their derivatives or paraffin and microcrystalline waxes.
• the preferred plasticizers useful in the present invention are for example, CATENEX N956, CATENEX S946, or EDELEX 945.
• composition according to the present invention may, but need not, contain a plasticizer. If it does, then the composition comprises up to 100 parts by weight, preferably 5 to 75 parts by weight, more preferably 10 to 40 parts by weight of a plasticizer.
• antioxidants can be used, either primary antioxidants like hindered phenols or secondary antioxidants like phosphite derivatives or blends thereof.
• examples of commercially available antioxidants are IRGA OX 565 from Ciba-Geigy (2.4-bis- (n-octylthio) -6- (4- hydroxy-3 , 5-di-tertiary-butyl anilino) -1,3, 5-triazine) , IRGANOX 1010 from Ciba-Geigy (tetrakis-ethylene- (3 , 5-di- tertiary-butyl-4-hydroxy-hydrocinnamate) methane) , IRGAFOS 168 from Ciba-Geigy or POLYGARD HR from Uniroyal (tris- (2 , 4-di-tertiary-butyl-phenyl) phosphite) .
• antioxidants developed to protect the gelling of the polybutadiene segments can also be use, like the SUMILIZER GS from Sumitomo (2 [1- (2-hydroxy-3 , 5-di-ter-pentylphenyl) - ethyl) ] -4, 6-di-tert-pentylphenylacrylate) ; SUMILIZER T-PD from Sumitomo (pentaerythrythyltetrakis (3-dodecylthio- propionate) ) ; or mixtures thereof. (IRGANOX, IRGAFOS, POLYGARD and SUMILIZER are trademarks) .
• the antioxidant which can be used in the present invention are IRGANOX 1010, IRGANOX 3052, IRGAFOS 168, SUMILIZER GS, SUMILIZER TPD .
• optimized antioxidant packages are a combination of IRGANOX 1010/lRGANOX 3052/IRGAFOS 168 or a combination of SUMILIZER GS/SUMILIZER TPD which gave stable hot melts at 180°C.
• Test methods have been performed on the adhesives in order to evaluate those of the present invention which are able to compete with acrylic tapes.
• the adhesive composition of (poly (styrene-butadiene-styrene) polymers having a high vinyl content in the butadiene blocks based packaging tapes) ideally should fulfill the following requirements: RBT: 1-5 cm (acceptable ⁇ 20 cm)
• Flap test 120-250 minutes (acceptable > 100 minutes)
• HP 40°C 50-100 minutes (acceptable > 40 minutes)
• HMV 100 Pa.s.
• the formulation 1 is a general formulation.
• Form. 1 100 phr SBS polymer / 125 phr HERCOTAC 205 / 40 phr CATENEX N956 / 1 phr IRGANOX 1010 / 1 phr IRGANOX 3052/1 phr IRGAFOS 168
• polymers with lower step I have been compared to polymers A to E. These polymers are F, G and H in table 1 and the characteristics of these polymers are indicated in that table 1.
• Table 3
• a formulation 2 is prepared with the SBS polymers F and G, but containing only 20 phr of the plasticizer CATENEXTM N 956.
• Form 2 100 phr SBS polymer / 125phr HERCOTACTM 205 / 20 phr CATENEXTM N956 / Iphr IRGANOXTM 1010 / Iphr IRGANOXTM 3052 / Iphr IRGAFOSTM 168
• the most suitable molecule is specified by the parameters hereunder which result in a MFR of 10.
• the target molecule has the following characteristics:
• Step I (kg/mol) 9,400-9,600, preferably about 9,500 vinyl (%) 25-40, preferably about 30 PSC (%) 16-19, preferably about 19 CE (%) 60-75, preferably about 70
• table 4 has been used the polymer G and in table 5 has been used the polymer H.
• compositions FIB and F4 furnish very valuable adhesives falling within the limits of properties desired for the adhesives of the present invention.

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• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Organic Chemistry (AREA)
• Health & Medical Sciences (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Inorganic Chemistry (AREA)
• Adhesives Or Adhesive Processes (AREA)
• Compositions Of Macromolecular Compounds (AREA)

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• 2003
  • 2003-03-24 BR BRPI0308687-9A patent/BR0308687B1/pt not_active IP Right Cessation
  • 2003-03-24 WO PCT/EP2003/003172 patent/WO2003080692A1/en active IP Right Grant
  • 2003-03-24 AU AU2003227547A patent/AU2003227547A1/en not_active Abandoned
  • 2003-03-24 CN CNA038093308A patent/CN1649924A/zh active Pending
  • 2003-03-24 DE DE60307243T patent/DE60307243T2/de not_active Expired - Lifetime

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