Polybutene-2-ethylene copolymer

Absorption at 13.3 pm which is characteristic of methylene sequences of two units is characteristic of a tail-to-tail configuration of ethylene and propylene units. This absorption is also found in polybutene-2-ethylene copolymer ... 

HDPE immiscibly blends with hutyl ruhher [14] to provide improved chemical resistance, compression set and high-temperatnre mechanical properties versus nnvnlcanised hlends. LDPE and HDPE blend immiscibly with ethylene copolymers to improve environmental stress crack resistance, tonghness, filler acceptance, film tear resistance, improved flexibility and so on. In polyolefin, polybntene-1 forms miscible blends with PP [15,16]. The addition of PP to polybutene-1 increases the crystallisation rate of polyhntene-1 and would have utility as a nucleation additive. 

The IR spectrum of amorphous alternating polybutene-1-ethylene copolymer shows absorptions at 13.3 pm (characteristic of methylene sequences of two units) and at 9 pm (characteristic of the structure). 

Copolymers of isobutene with styrene (< 10 %) and isoprene (< 3 %) may be used for the manufacture of food contact materials. The following polymerizates and polymer mixes can be added to these polymerizates polyethylene, polypropylene, styrene-acrylonitrile mixed polymers, mixed polymers of ethylene, propylene, butylene, vinyl esters and unsaturated aliphatic acids as well as salts and esters and polybutene-1. 

The most widely used thermoplastic polymer is the ethylene—vinyl acetate copolymer, which is obtainable in a wide range of molecular weights as well as in a variety of compositions. Often flexibilizers or plasticizers are added in order to improve both the mechanical shock resistance and the thermal properties of the adhesive. Polybutenes, phthalates, and tricresyl phosphate have been used as plasticizers. Tackifying agents can also be added. Because hot-melt adhesives are frequendy ethylene-based, they are subject to oxidation if, as in a typical situation, the adhesive sits in an applicator for long periods before use. Thus, antioxidants such as hindered phenols are often used, as are fillers. Fillers are added to opacify or to modify the adhesive s flow characteristics, as well as to reduce cost. Wax is also a very important component. Wax alters surface characteristics by decreasing both the liquid adhesive s surface tension and its viscosity in the melt. Upon solidification, however, the wax acts to increase the strength of the adhesive. Both paraffin and microcrystalline wax are used (see Waxes). 

Polyethylene and polypropylene are the polyolefins most commonly used as plastics. Polybutene-1 and poly-4-methylpentene-l are less common. Also important are certain copolymers of ethylene and also polyisobutylene, which is used for gaskets. The simplest method of identification of these materials is by infrared spectroscopy (see Section 8.2). However, some information can also be obtained from the melting range (see also Section 3.3.3) ... 

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. ... 

The partial molar quantities of mixing were determined for normal and branched alkanes (O5 — Cio), cyclohexane, benzene and tetrachloromethane in polyisobutylene [57]. Partial molar enthalpies of mixing were measured for normal alkenes in low and high density polyethylene, polypropylene, polybutene-1, polystyrene, poly(methyl acrylate), poly(vinyl chloride), polyCN-isopropyl-acrylamide), ethylene-vinyl acetate copolymer, ethylene-carbon oxide copolymer [88] normal, branched and cyclic alkanes, benzene, n-butylbenzene, ois- and ra s-decalin, tetraline and naphthalene in polystyrene at 183, 193 and 203°C [60] these solutes in poly (methyl acrylate) [57] n-nonane, n-dodecane and benzene in polystyrene in the range 104.8 — 165.1 C [71] O7—C, C12 normal alkanes and aromatic hydrocarbons in polystyrene at an average temperature of 204.9°C [72], C7—Cg normal alkanes in poly(ethylene oxide) at an average temperature of 66.5 "C [72] normal alkanes in ethylene oxide—propylene oxide block copolymers (Pluronics L 72, L 64 and F 68) at the same average temperature [72]. 

Blends. Blends of iPP with poly(styrene)-6Zoc -poly(ethylene-co-l-butene) were prepared imder various conditions and imaged by afm, where macrophase separation because of incompatibility of the components was observed (Fig. 17). The degree of phase segregation was shown to be dependent on the thermal history of the sample (118). Blends of iPP and different poly(ethylene-butene) (PEB) copolymers were imaged. The authors foimd that iPP and PEB containing 88% butene were miscible, and PEB containing <88% butene were partially to totally immiscible, and polybutene (100% butene) was partially miscible. So, there is a narrow window of miscibility for these blends (119). 

Differential thermal analysis has been used for the measurement of crystallinity of random and block ethylene-methacrylate copolymers [30] and of polybutene [31], PET, 1,4-cyclohexanedimethyl terephthalate, and polypropylene (PP) [32, 33] and in the examination of morphologically different structures of PE ionomers [34]. 

Figure 12.32 Plot of brittle stress at about — 180 °C against a line joining yield-stress values at —20 °C (o), respectively, for various polymers. Line A divides polymers that are brittle unnotched from those that are ductile unnotched but brittle notched, and line B divides polymers that are brittle notched but ductile unnotched from those that are ductile even when notched. PMMA, poly(methyl methacrylate) PVC, poly(vinyl chloride) PS, polystyrene PET, poly(ethylene terephthalate) SAN, copolymer of styrene and acrylonitrile CA, cellulose acetate PP, polypropylene N, nylon 6 6 LDPE, low-density polyethylene POM, polyoxy-methylene PB, polybutene-1 PC, polycarbonate PTFE, polytetrafluoroethylene. (Reproduced with permission from Vincent, Plastics, 29, 79 (1964))...

SEBS was used to compatibilize PP with either PS or HIPS. The blends showed good impact and flexural strength [34]. Addition of SEBS was found to be expensive but useful in many recycling processes. Other compatibilizers for commingled polymeric scrap containing PS and PO and other resins, are CSR, SBR, (SB)n block copolymers, polybutylene-1, a copolymer of butylene-1 and ethylene, isotactic polybutene [3], etc. 

Physical blends of the two homopolymers, PE and polybutene-1 will not suffice because these have a different spectrum to a true copolymer with the same ethylene-butane ratio. An excellent method for preparing such standards is to copolymerise blends of ethylene and C-lahelled butane-1 of known activity. From the activity of the copolymer determined hy scintillation counting, its butane-1 content can be calculated. 

This is found in amorphous ethylene-propylene alternating copolymers, polybutene-2-ethylene alternating copolymer, and hydrogenated poly 2,3-dimethyl butadiene ... 

ESR spectroscopy has been applied to studies of unsaturation and other structural features in a wide range of homopolymers including polyethylene [101-110], polypropylene [111-121], polybutenes [115], polystyrene [122-124], PVC [125,126], polyvinylidene chloride [127], polymethylmethacrylate [128-137], polyethylene glycol polycarbonates [137-140], polyacrylic acid [136-139, 141, 142], polyphenylenes [143], polyphenylene oxides [143], polybutadiene [144], conjugated dienes [145,146], polyester resins [146], cellophane [143,147] and also to various copolymers including styrene grafted polypropylene [148], ethylene-acroline [149], butadiene-isobutylene [150], vinyl acetate copolymers [151] and vinyl chloride-propylene. 

Benefos 1680 is a secondary antioxidant. It is particularly useful in polyolefins and olefin-copolymers such as polyethylene, polypropylene, polybutene and ethylene vinyl acetate copolymers as wall as polycarbonate and polyamids. Other applications Include use in linear polyesters, high impact polystyrene, ABS, SAN, adhesives, natural and synthetic tackifier resins, elastomers such as BR, IR, euid other organic siibstrates. 

PB base polymers are semicrystalUne isotactic thermoplastic polyolefins. They are derived from the polymerization of butene-1 monomer with or without other alpha-olefin monomers utilizing a Ziegler-Natta type of catalyst. Their unique crystallization behavior means longer open times of adhesive and sealant formulations compared to other commonly used polymers such as polyethylene and ethylene-vinyl acetate copolymer (EVA). Polybutylene (PB), also called polybutene-1 or poly-1-butene, is different from polybutene or polyisobutylene (PIB). PIB is amorphous and rubbery, and comes in the form of a viscous liquid or big, hard block (6 in. in length and width or could be larger). PB base polymers are sup-pUed in the form of small pellets (about 0.25 in. in diameter) or nibs. 

Peroxides can be used to crosslink diene elastomers, polyethylene, and ethylene propylene copolymers. With polyolefins such as polypropylene, polybutene, and polystyrene, they induce degradation. 

To check the correctness of this interpretation von Schooten and co-workers [7] examined the IR spectrnm between 13 and 14 pm of ethylene-propylene copolymers prepared with varions catalyst systems and compared them with the spectra of some model componnds, namely 2,5-dimethylhexane, 2,7-dimethyloctane, 4-methylpentadecane, 4-n-propyltridecane, polypropylene, polyethylene, polybutene-1 and hydrogenated polyisoprene, the last being considered as an ideally alternating ethylene-propylene copolymer. 

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