Octene comonomer

In their study on LLDPE resins containing 1-butene, 1-hexane, and 1-octene comonomers, Kalyon and Moy [30] found a significant variation in their film thickness when measured around the circumference of tubular bubbles processed under identical conditions. The samples blown with a blow-up ratio of two, exhibited more significant variation in thickness than those prepared with a blow-up ratio of three. However, film processed at a higher blow-up ratio has been found to have less variation in thickness. 

Extremely soft and fluid blends of E-plastomers with iPP have been made by incorporating a large amount of a low-density E-plastomer with added process oil for fluidity and softness with a minor amount of iPP [10]. In a representative formulation, 56 parts of an impact copolymer (ICP) which had 62 wt% of iPP and the balance an EPR, 22 parts of an E-plastomer (hexene comonomer), 11 parts of an E-plastomer (octene comonomer), and 5 parts of talc showed a Rockwell R hardness 77,... 

The effect of oxidative irradiation on mechanical properties on the foams of E-plastomers has been investigated. In this study, stress relaxation and dynamic rheological experiments are used to probe the effects of oxidative irradiation on the stmcture and final properties of these polymeric foams. Experiments conducted on irradiated E-plastomer (octene comonomer) foams of two different densities reveal significantly different behavior. Gamma irradiation of the lighter foam causes stmctural degradation due to chain scission reactions. This is manifested in faster stress-relaxation rates and lower values of elastic modulus and gel fraction in the irradiated samples. The incorporation of O2 into the polymer backbone, verified by IR analysis, conftrms the hypothesis of... 

The general structure of linear low density polyethylene is shown in Fig. 18.2 c). Linear low density resins are copolymers of ethylene and 1-alkenes principally 1-butene, 1-hexene, and 1-octene. Comonomer levels range from approximately 2 to 8 mole %. This family of polyethylene is widely known as LLDPE. Linear low density polyethylenes are polydisperse with regard to molecular weight and branch distribution. 

To illustrate this relationship, consider a random ethylene copolymer of a density 0.856 g cm-3 containing about 19 mol% 1-octene comonomer. At room temperature,... 

Figure 15. Initial slopes of the stress growth functions of LLDPE s (containing butene, hexene or octene comonomer) as function of resin polydlsperslty.

Type of branches—1-butene comonomer gives ethyl branches, 1-hexene comonomer gives butyl branches, and 1-octene comonomer gives hexyl branches. The length of branches has a small influence, but the number of branches is more important since the branches do not take part in crystallization. 

The CG catalysts produce highly processable polyolefins with a unique combination of narrow MWD and long chain branches. Ethylene-octene copolymers produced with CG catalysts have useful properties across a range of densities and melting indexes. These novel copolymer families are called polyolefin plastomers (POP) and polyolefin elastomers (POE). POPs possess plastic and elastic properties while POEs containing greater than 20 wt% octene comonomer units have higher elasticity. 

General Description Dow Chemicals Affinity resins, homogenous ethylene alpha-olefin copolymers, contain up to 20% octene comonomer. Affinity polyolefin plastomers (POPs) can be used in any of the extrusion technologies as a sealant, to deliver an unparalleled combination of low seal-initiation temperature, hot-tack strength, toughness, tear resistance, and transparency.f ... 

Polyethylene (PE) is inherently less sensitive to oxidative attack than PP, but stabilization of PE is also mandatory for outdoor use. The stability varies with the type of polyethylene and manufacturing process. Linear low-density polyethylene (LLDPE) (1-octene comonomer) is significantly less sensitive to photooxidation than low-density polyethylene (LDPE) with comparable density and molecular weight [20, 21]. Generally, LDPE is less susceptible to photooxidation than high-density polyethylene (HDPE). The most fundamental difference between polyethylene homopolymers and polypropylene is the behavior of hydroperoxides toward photolysis. On photooxidation, hydroperoxides accumulate in PP, but decrease rapidly on UV exposure of PE. In copolymers of polyethylene with vinyl acetate, the stabihty depends on the content of vinyl acetate. The higher the content, the more the copolymers act like polyvinyl acetate, which is more susceptible to photooxidative degradation than polyethylene. 

Khare, R.A., Kulkarni, A.R., Saroop, M., and Biswas, A. (2009) Blends of polypropylene and ethylene octene comonomer with conducting fillers influence of state of dispersion of conducting flllers on electrical conductivity. Polym. Bt g. Sci., 49, 1502. 

Enhanced PE. The Affinity resins range in density from 0.902 to 0.935 gcm , in weight percent comonomer from 2 to 12% octene comonomer, and melt index (Ml) from 1.0 to 3.5 g (10min) . ... 

Polymer crystals are rarely perfect and can include chain ends, voids, and at times short-chain branches. As it is generally concluded that the ethyl branch from butene comonomers can be incorporated into the crystal lattice (24-28), this may explain why longer comonomers give LLDPEs with improved properties. Hexene and octene comonomers are more likely to produce large fold loops or tie chains that improve toughness. Quick quenching from the melt also provides less perfect crystals and may allow longer branches to be included in the crystal lattice (29). 

The workhorse resin used by many extruders is an octene comonomer linear low-density resin with a nominal density of 0.920 g/cuP and a melt index of 0.1 g/min. This resin offers a combination of reasonable clarity and toughness. It is also easy to process on most extrusion and converting equipment. 

To illustrate this relationship, consider a random ethylene copolymer of a density 0.856gcm" containing 19mol.% 1-octene comonomer. At room temperature, the material is elastic, or capable of recovering its size and shape after deformation. However, the copolymer loses the desirable properties of an elastomer at higher temperatures for example, the material has a compression set, a measure of a material s ability to recover its size after compression, of 100% at 70 °C (Figure 2). The ability to make PE with properties that fall outside these limitations would lead to a tremendous expansion of uses for this polymer, for example, replacing flexible polyvinylchloride (f-PVC), which cannot be incinerated or recycled, or more expensive thermoplastic polyurethanes (TPUs) or thermoplastic vulcanizates (TPVs). 

The NMR resonances are sensitive to structural contributions of carbon atoms up to about four atoms away from a given atom. As a result, this technique is unable to detect, for example, the difference between a short-chain branch resulting from the presence of octene comonomer in polyethylene and a branch long enough to be entangled. When dealing with a polymer that contains both types of branch, additional techniques are required to elucidate the structure. 

The first reactors used to make HOPE were based on a solution process. This had the advante es of small reactor size, short residence time, and the possibility of removing catalyst particles from the product by filtration or centrifugation. Dupont Canada later took advantage of the high operating temperature, 150 °C, for the incorporation of octene comonomer to make Sclair LLDPE. 

Octene comonomer slow cooled A Octene comonomer quenched... 

---