Poly butene Density

Properties of Poly butene Sulfone Foam. Many properties of polybutene sulfone foam are similar to those of polystyrene foam. Mechanical properties are a little lower for the same foam density, but the bulk density of polybutene sulfone is 1.37 compared with 1.05 for polystyrene. Figure 6 shows that mechanical properties vary in the same ratio as density The insulating properties of polybutene sulfone foam are very good, somewhat better than polystyrene foam (Figure 7). Polybutene sulfone has a good solvent resistance as shown in Table I. In particular, styrene, benzene, and toluene do not attack polybutene sulfone but attack polystyrene. 

Isotactic poly(butene-l) is produced commercially with three-component coordination-type catalysts. It is manufactured by a continuous process with simultaneous additions to the reacticMi vessel of the monomer solution, a suspension of Ti l2-Al l3, and a solution of diethyl aluminum chloride [84], The effluent containing the suspension of the product is continually removed from the reactor. Molecular weight control is achieved through regulating the reaction temperature. The effluent contains approximately 5-8% of atactic polybutene that is dissolved in the liquid carrier. The suspended isotactic fractions (92-98%) are isolated after catalyst decomposition and removal. The product has a density of 0.92 g/cnf and melts at 124—130° . 

LLFPE, LDPE, HDPE—linear low density, low density, and (respectively) high density poly(ethylene) PP—poly(propylene) PB-1—poly-(butene-1) PIB—poly(isobutylene) P4MP—poly(4-methylpentene-l) EP—ethylene-propylene copolymers EVA—ethylene-vinylacetate copolymers. 

In a few cases, the addition of minor amounts of immiscible or miscible polymers results in the nucleation of a crystalline polymer. The nucleation of PP by PE and polyamides (e.g., PAl 1) (immiscible) as well as the addition of PP to poly(butene-l) (miscible) has been noted in the literature [138-141 ]. The addition of LDPE to PP showed a reduction in the spherulite size of PP, attributed to an increase in nucleation density of the a-crystalline form along with an increase in the rate of growth of the -crystalline form [141]. The nucleation of polycarbonate by the zinc salt of sulfonated polystyrene ionomers was noted to occur with both miscible and phase separated blends [142]. Nanometer sized ionic aggregates appeared to contribute to the polycarbonate nucleation. A liquid crystalline copolyesteramide (Vectra-B950 ) was shown to accelerate the crystallization of poly(phenylene sulfide) [143]. This effect was not concentration dependent and did not change the level of crystallinity. 

The principal polyolefins are low-density polyethylene (ldpe), high-density polyethylene (hope), linear low-density polyethylene (lldpe), polypropylene (PP), polyisobutylene (PIB), poly-1-butene (PB), copolymers of ethylene and propylene (EP), and proprietary copolymers of ethylene and alpha olefins. Since all these polymers are aliphatic hydrocarbons, the amorphous polymers are soluble in aliphatic hydrocarbon solvents with similar solubility parameters. Like other alkanes, they are resistant to attack by most ionic and most polar chemicals their usual reactions are limited to combustion, chemical oxidation, chlorination, nitration, and free-radical reactions. 

We have studied the alkane and alkene yields from the radiolysis of copolymers of ethylene with small amounts of propylene, butene and hexene. These are examples of linear low density polyethenes (LLDPE) and models for LDPE. Alkanes from Ct to C6 are readily observed after irradiation of all the polymers in vacuum. The distribution of alkanes shows a maximum corresponding to elimination of the short-chain branch. This is illustrated in Figure 8 for the irradiation of poly (ethylene-co-1-butene) containing 0.5 branches per 1,000 carbon atoms at 20 C. 

The commercial production of high-density polyethylene started almost at the same time in late 1956 by Phillips using a chromium-based catalyst in a medium-pressure process and by Hoechst using a Ziegler catalyst in a low-pressure process. Polypropylene production began in Montecatini and Hercules plants in 1957. Poly(l-butene) and poly(4-methyl-1-pentene) have been produced in small commercial quantities since about 1965. The commercial production of ethylene/propylene-based rubbers started in 1960 [241]. 

Chen, S.-J. and Radosz, M., Density-tuned polyolefin phase equihbria. 1. Binary solutions of alternating poly(ethylene-propylene) in subcritical and supercritical propylene, 1-butene and 1-hexene. Experimental and Flory-Patterson model, Macrontolecules, 25, 3089-3096, 1992. 

BYU Byun, H.-S., Kim, K., and Lee, H.-S., High-pressure phase behavior and mixture density of binary poly(ethylene-co-butene)-dimethyl ether system, Hwahak Konghak, 38, 826, 2000. 

LID Li, D., McHugh, M.A., and van Zanten, J.H., Density-induced phase separation in poly(ethylene-co-l-butene)-dimethyl ether solutions, Macromolecules, 38, 2837, 2005. 

Tg was measured by gas-chromatography in the following polyolefines crystalline-amorphous polypropylene [1], isotactic, atactic and syn-diotactic polypropylene [170], polyethylene of various densities, polyiso-butene and poly(l-butene) [130], polybutadiene [206]. 

The heat distortion temperature at 1.80 Mpa is the temperature that causes a beam loaded to 1.80 to deflect by 0.3 mm. If the heat distortion temperature is lower than the ambient temperature, -20 C is given. Polymers such as low-density polyethylene, styrene ethylene-butene terpolymer, ethylene-vinyl acetate copolymer, polyurethane, and plasticized polyvinyl chloride distort at temperatures below <50°C, whereas others, such as epoxies, polyether ether ketone, polydiallylphthalate, polydiallyl isophthalate, polycarbonate, alkyd resins, phenol formaldehyde, polymide 6,10 polyimide, poly-etherimides, polyphenylene sulfide, polyethersulfone, polysulfonates, and silicones, have remaikably high distortion temperatures in the range of 150°C to >300 C. Thermomechanical analysis has been used to determine the deflection temperature of polymers and sample loading forces (i.e., plots of temperature vs. flexure). 

The widely investigated Phillips catalyst, which is alkyl free, can be prepared by impregnating a silica-alumina (87 13 composition [101-103] or a silica support with an aqueous solution of Cr03). High surface supports with about 400 to 600 g/m are used [104]. After the water is removed, the powdery catalyst is fluidized and activated by a stream of dry air at temperatures of 400 to 800 °C to remove the bound water. The impregnated catalysts contain 1 to 5wt% chromium oxides. When this catalyst is heated in the presence of carbon monoxide, a more active catalyst is obtained [105]. The Phillips catalyst specifically catalyzes the polymerization of ethene to high-density polyethene. To obtain poly ethene of lower crystallinity, copolymers with known amounts of an a-olefin, usually several percent of 1-butene ean be synthesized. The polymerization can be carried out by a solution, slurry, or gas-phase (vapor phase) process. 

Isotactic poly(l-butene) crystallizes from the melt into an unstable modification which is slowly converted into a thermodynamically more stable form. The two modifications differ in helical structure and density therefore, the product undergoes deformation in the course of time [515,516]. For the polymerization of butene the same catalysts are used as for propene. 

Common name - linear low density polyethylene poly(ethylene-co-l-octene) poly(ethylene-co-1 -butene) poly(ethylene-co-1 -hexene) ... 

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