Polyolefins ethylene-propylene copolymer

The use of TAG as a curing agent continues to grow for polyolefins and olefin copolymer plastics and mbbers. Examples include polyethylene (109), chlorosulfonated polyethylene (110), polypropylene (111), ethylene—vinyl acetate (112), ethylene—propylene copolymer (113), acrylonitrile copolymers (114), and methylstyrene polymers (115). In ethylene—propylene copolymer mbber compositions. TAG has been used for injection molding of fenders (116). Unsaturated elastomers, such as EPDM, cross link with TAG by hydrogen abstraction and addition to double bonds in the presence of peroxyketal catalysts (117) (see Elastol rs, synthetic). 

The radical initiated copolymerization of C2H4 and CO in the presence of a polyolefin has been reported to result in the grafting of the C2H —CO copolymer onto the polyolefin backbone31). Polyolefins used included polyethylene, ethylene-propylene copolymer and polyisobutylene. 

The mechanism of degradation and stabilization of ethylene-propylene copolymers broadly resembles that of polyolefins yet there are major differences arising mainly from their distinct chemical composition and structure. Although voluminous literature has accumulated in this area [10 12], there is no concise compilation and organization of this literature. 

Since the discovery of olefin polymerization using the Ziegler-Natta eatalyst, polyolefin has become one of the most important polymers produeed industrially. In particular, polyethylene, polypropylene and ethylene-propylene copolymers have been widely used as commercial products. High resolution solution NMR has become the most powerful analytieal method used to investigate the microstructures of these polymers. It is well known that the tacticity and comonomer sequence distribution are important factors for determining the mechanical properties of these copolymers. Furthermore, information on polymer microstructures from the analysis of solution NMR has added to an understanding of the mechanism of polymerization. 

Catalytic hydrogenation with cobalt/aluminum catalyst gave polyethylene copolymers (from the hydrogenation of butadiene copolymers) or ethylene/propylene copolymers (from isoprene copolymers) containing 2,6-ditertiarybutyl-il--vinylphenol or 2,6-ditertiarybutyl-4-iso-propenylphenol in the polymer. These polymers have been used as polymeric antioxidants and axe effective in retarding autooxidation of polyolefins ( 0). 

The same technique can be used to dye a material that is otherwise difficult to dye. An ethylene-propylene copolymer rubber was reacted first with maleic anhydride, then with an aromatic amine dye in an extruder to produce a dyed rubber.81 Dye sites can also be inserted into polyolefins by grafting them with dimethylaminoethyl methacrylate, using azo or peroxide catalysts in an extruder.82 jV-Vinylimidazole has been grafted to polyethylene in an extruder with the help of dicumylperoxide.83 The product was mixed with an acrylic acid-modified polypropylene and used to compatibilize polyethylene and polypropylene. This could be helpful in the recycling of mixed polyolefins from municipal solid waste. Recycling of cross-linked (thermoset) polymers is more of a problem because they cannot be remelted in an extruder. However, they can be if... 

ADK Stab LA 77 Bis(2,2,6,6-tetramethyl-4-piperidinyl) decanedioate Bis(2,2,6,6-tetramethyl-4-piperidinyl)-sebacate Decanedioic acid, bis 2,2,6,6-tetramethyl-4-piperidinyl) ester EINECS 258-207-9 HALS 1 HALS 770 Lowilite 77 LS 770 Mark LA 77 Sanol Sanol 770 Sanol LS 700 Sanol LS 770 Sumisorb 577 T 770 TIN 770 Tinuvin 770 Tinuvin 770DF Tinuvin 770LS TK-10665 Uvaseb 770. Light stabilizer for polyolefins, ABS, PUR acrylics, PS and styrene copolymers, thermoplastic elastomers, ethylene-propylene copolymers, polyamides. Ciba-Geigy Corp. En/Chem SpA bowi. 

The results from the in situ X-ray study of propylene-based ethylene-propylene copolymer during tensile deformation (36) are described as follows, because the deduced molecular mechanism appears to be universal in all elastomeric polyolefin copolymers. The stress-strain curves and selected WAXD patterns during extension up to strain 5.0 and subsequent retraction back to strain 1.7 (i.e., at zero stress) in the first deformation cycle are shown in Fig. 8.22. 

Among the most commonly utilized synthetic polymers are polyolefins, such as polyethylenes (PEs), polypropylenes (PPs), and ethylene-propylene copolymers (P(E-co-P)s). Despite their simple elemental compositions, consisting of only carbon and hydrogen, it is well known that their physical properties are quite dependent on the microstructural features, such as short- and long-chain branchings, stereoregularities, chemical inversions of monomer enchainment, sequence distributions, etc. ... 

N nylon, PO polyolefin, elastomer, TPU thermoplastic urethane, GF glass fiber, NBR nitrile rubber, MAH maleic anhydride, EPR ethylene-propylene copolymer, l ionomer, M- mineral, ABS acrylonitrile-butadiene-styrene copolymer, PPE poly (phenylene ether), R reinforcement, PTFE poly(tetrafluoroethylene), CF° carbon fiber, PEBA poly(etherblockamide), S silicone, RIPP D reaction injection molding plastic, and ASA acrylate-styrene-acrylonitrile copolymer. 

Semicrystalline polyolefin blends and method of their preparation were described. The blends were reported to show enhanced inter-spherulitic and interlamellar strength. The first polymer should have higher crystallinity and crystallization temperature than the second. Thus, 50-99.9 wt% PP was blended with ethylene-a-olefin copolymers, either a stereo block polypropylene or an ethylene-propylene copolymer, EPR... 

Thermoplastic polyolefin (TPO) elastomers are typically composed of ethylene propylene rubber (EPR) or ethylene propylene diene M (EPDM) as the elastomeric segment and polypropylene thermoplastic segment. LDPE, HDPE, and LLDPE copolymers ethylene vinyl acetate (EVA), ethylene ethylacrylate (EEA), ethylene, methyl-acrylate (EMA) and polybutene-1 can be used in TPOs. Hydrogenation of polyisoprene can yield ethylene propylene copolymers, and hydrogenation of 1,4- and 1,2-stereoisomers of S-B-S yields ethylene butylene copolymers. ... 

Polyamide (PA)/maleic-anhydride (MA)-functionalised polyolefin (PO) blends provide a compatibility strategy consisting of maleation of the PO phase followed by a reactive processing favouring copolymer formation by imidisation between the anhydride and amine chain ends. The PO is most often ethylene-propylene copolymer rubber, PP or PE, and the PA is commonly PA6 or PA6,6 [49-58]. 

The major types of impact modifiers are acrylics, styrenics including methacrylate-butadiene-styrene (MBS) copolymers and Acrylonitrile-Butadiene-Styrene Polymers, chlorinated polyethylene (CPE), EVA copolymers, and the ethylene-propylene copolymers and terpolymers (EPR and EPDM respectively). The major market for impact modifiers is in PVC, although they are used in a wide range of other polymers such as polyolefins and engineering polymers. 

I. Valvassori, A. Zambelli, A. Copolymers of ethylene, higher a-olefins, and monocyclomonool-efins or aUcyl derivatives thereof. U.S. Patent 3,505,301 (Montecatini Edison S.p.A.), April 7, 1970. (b) Zambelli, A. Tosi, C. Sacchi, C. Polymerization of propylene to syndiotactic polymer. VI. Monomer insertion. Macromolecules 1972, 5, 649-654. (c) LocateUi, R Immirzi, A. Zambelli, A. Palumbo, R. Maglio, G. Orientation of propylene units in polypropylene and ethylene/propylene copolymers. Makromol. Chem. 1975,176, 1121-1128. (d) Carman, C. J. Harrington, R. A. Wilkes, C. E. Monomer sequence distribution in ethylene-propylene rubber measured by C NMR. 3. Use of reaction probability mode. Macromolecules 1977, 10, 536-544. (e) Zucchini, U. Dall Occo, T. Resconi, L. Ziegler-Natta catalysis for the polyolefin industry Present status and perspectives. Indian... 

A second functionalization approach was based on the insertion of carbenes into the C-H bond (Scheme 3). The reaction of different polyolefins, such as high density polyethylene (HDPE), atactic polypropylene (aPP), isotactic polypropylene (iPP), ethylene-propylene copolymers (EP) and polyisobutene (iPBu) with diazoesters at 210T in bulk has been shown to give a product containing the carboxylate functionality attached to the polymer backbone. The presence of the functional groups in the polymer was inferred by IR spectroscopy (carbonyl stretching band at 1740 cm "1 and in case of chloroethyldiazoacetate... 

---