Polypropylene, surface modified

Posudiyevskii, O. Yu., Myasnikova, I. G., and Chuiko, A. A., Optical properties of the polypropylene surface modified by implantation of fluorine ions (in Russian), Dokl. Akad. Nauk SSSR, 319, 196-199 (1991). 

Figure 29. Fiuman osteoblast-like MG 63 cells in cultures on material surfaces modified with carbon nanoparticles. A fullerene Cgo layers deposited on carbon fibre-reinforced carbon composites (CFRC), B fullerene C o layers deposited on microscopic glass coverslips, C terpolymer of polytetrafluoroethylene, polyvinyldifluoride and polypropylene, mixed with 4% of single-wall carbon nanohorns, D the same terpolymer with high crystalline electric arc multi-wall nanotubes, E diamond layer with hierarchically organized micro- and nanostmcture deposited on a Si substrate, F nanocrystalline diamond layer on a Si substrate. Standard control cell culture substrates were represented by a PS culture dish (G) and microscopic glass coverslip (FI). Immunofluorescence staining on day 2 (A) or 3 (B-Fl) after seeding, Olympus epifluorescence microscope IX 50, digital camera DP 70, obj. 20x, bar 100 pm (A, C, D, G,H)or 200 pm (B, E, F) [16].

Conference, 2001) printed antiinterleukin monoclonal antibodies in the bottom of a prototype shallow, vacuum-formed, 96-well polypropylene plate (Figure 6.9). The plastic was surface modified with acyl fluoride groups for rapid and efficient covalent attachment of the antibodies. 

Another kind of solid support that has gained more popularity is the surface-modified polypropylene, such as the Multipin crown and Microtubes. Reaction 3 was carried out on lightly and highly cross-linked polystyrene resins (1 % and >20% divinylbenzene, respectively), poly sty rene-PEG resin, and a surface-functionalized Microtube reactor.12 The reaction kinetics on these supports is compared in Figures 7.4 and 7.5. The reaction on the highly cross-linked polystyrene resin was shown to be slower than on other supports and the reaction on Microtube was faster than on polystyrene resins. 

TABLE 1. Shear bond testing of surface modified polypropylene after oxyflnorination curing in mortar slurry. 

Surface modifiers are used for a number of reasons, and these include reduction of dustiness and moisture content, improved processing, and enhanced composite properties. Table 11.1 shows that filling polypropylene with uncoated magnesium hydroxide results in a significant decrease in impact and flexural strength. However, surface treatment of the filler can counteract these effects to some degree. 

Talc - Talc is a filler made by dry or wet grinding of mineral magnesium silicate. Talc improves stiffness, dimensional stability, flexural modulus, creep resistance, flow, surface smoothness, moisture resistance, tensile strength, and wear resistance of plastics. It also increases heat deflection temperature and decreases vapor permeability. Can be used as a film antiblock agent. Used mainly in polypropylene but also in thermoplastic and unsaturated polyesters and epoxy resins at low levels. Surface-modified grades are available. 

The effects of the reduced and modified mechanism (Table 22.1) on the functional groups found on the polypropylene surface are given in Figure 22.16. In comparison to the original plasma treatment mechanism [33], the reduced and modified reaction mechanism presented by Stroud and Branch [34] yields surface species functionalities that are more consistent with the data available from the most recent studies [31,32]. In comparing... 

Velasco, J.I., Desaja, J.A., Martinez, A.B. Crystallization behavior of polypropylene filled with surface-modified talc. J. Appl. Polym. Sci. 61, 125-132 (1996)... 

Natural fiber-reinforced polyolefins are commonly apphed to automotive and constmction applications. The most abundantly used additive is fire retardant. Flammability is an important factor that often limits the application of composites to a specified field. Magnesium hydroxide is the most common flame retardant material used in the constmction industry. This filler responds well to surface modifiers and decomposes by an endofliermic reaction that releases water at temperatures close to the polymer degradation temperature as show in Eq. 6.1. Rothon et al. [78] studied the effects of magnesium hydroxide on polypropylene as a flame retarder of 60 % by weight. The smdy found less heat emission at 100 kWm after 6 min of fire exposure compared to filled PP without Mg(OH)2 at 500 kWm. ... 

A.K. Gupta, M. Biswal, S. Mohanty, S.K. Nayak, Mecharncal, thtamal degradation, and flammability studies on surface modified sisal fiber reinfOTced recycled polypropylene composites. Adv. Mech. Eng. 2012, 13 (2012)... 

Lam, T. D. Hoang, T. V., Quang, D. T. Kim, J. S. (2009). Effect of nanosized and surface-modified precipitated calcium carbonate on properties of CaC03/polypropylene nanocomposites. Materials Science and Engineering Part A, Vol. 501, pp. (87-93)... 

Fig. 114. Percentage of the viscoelastic retention on endothelial cells of the rabbit and on a polypropylene surface after irrigation and aspiration (n=6 up to n=9) (modified according to Poyer et al., 1998)...

In the last decade, considerable progress was observed in the field of PO/compatibil-izer (predominantly on the base of PO-g-MA)/organo-surface-modified clay nanocomposites. Polyethylene (PE), polypropylene (PP), and ethylene-propylene (EP) rubber are one of the most widely used POs as matrix polymers in the preparation of nanocomposites [3,4,6,30-52]. The PO silicate/silica (other clay minerals, metal oxides, carbon nanotubes, or other nanoparticles) nanocomposite and nanohybrid materials, prepared using intercalation/exfoliation of functionalized polymers in situ processing and reactive extrusion systems, have attracted the interest of many academic and industrial researchers because they frequently exhibit unexpected hybrid properties synergisti-cally derived from the two components [9,12,38-43]. One of most promising composite systems are nanocomposites based on organic polymers (thermoplastics and thermosets). 

Mixture surface plot of tensile modulus and of the polypropylene organically modified montmorillonite composites as a function of mixture components. (Reproduced from Mittal, V., /. Thermoplast. Compos. Mater., 21, 9, 2008a. With permission from Sage Publishers.)... 

Haworth, B. and Raymond, C.L. (1997) Processing and fracture characterisation of polypropylene filled with surface modified calcium carbonate. Proceedings of the Eurofillers 97 Conference, Manchester, UK, September 1997,... 

Extrusion rates are also increased by use of surface treated mica (6). The extrusion rate increased 20% for a 50 wt% filled polypropylene homopolymer compound using surface-modified mica. 

A comparison of the properties of surface-treated phlogopite mica with talc, calcium carbonate, glass, and the unfilled resin is given in a technical bulletin produced by Marietta Resources International, Ltd. (10). Table 14.7 shows that 40 wt% mica-filled polypropylene (Profax 6523) had a higher flexural modulus than 30 wt% glass fiber-filled polypropylene (1.04 X 10 psi versus 0.93 X 10 psi). The compound filled with 40 wt% surface-modified mica also had higher Izod impact than the 40 wt% talc-filled compound (0.65 versus 0.45 ft-lb/in). 

Table 14.7 Surface-Modified Phlogopite Mica vs. Other Minerals for Polypropylene Reinforcement...

Table 14.32 Impact Comparisons for Talc- and Surface-Modified Mica in Polypropylene...

KR Marshall, RE Duncan. Study of surface-modified mica in polypropylene. 38th Annual Conference, Houston, TX, RP/C SPI, 1983. 

Graft copolymers between unsatnrated acids, especially acrylic acid and maleic anhydride (MA), and polyolefins (PE and PP) are widely used as surface modifiers and compatibilisers, sometimes in combination with bi-functional coupling agents [46], for talc, calcium carbonate and calcined clays. Such polymer coatings include polypropylene-maleic anhydride [47], polypropylene c/s-4-cyclohexene-l,2 dicarboxylic acid [48], polystearyl or polylauryl acrylate [49], polypropylene-acrylic acid, partially oxidised poly(butane diol) [50] and ethylene-vinyl acetate copolymers [51]. Acid-containing products can react with basic fillers. With most other types, they will simply adsorb on to the mineral surface, but they can form esters with some non-basic metal hydroxyls, notably silanols. 

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