Grafting with acrylic acid

Dielectric relaxation measurements of polyethylene grafted with acrylic acid(AA), 2-hydroxyethyl methacrylate (HEMA) and their binary mixture were carried out in a trial to explore the molecular dynamics of the grafted samples [125]. Such measurements provide information about their molecular packing and interaction. It was possible to predict that the binary mixture used yields a random copolymer PE—g—P(AA/HEMA), which is greatly enriched with HEMA. This method of characterization is very interesting and is going to be developed in different polymer/monomer systems. 

Figure 12 and 13. ESCA spectra of polyethylene split film before. grafting (A), after presoaking in sensitizer-monomer solution (B) and after grafting with acrylic acid (8 sec., Figure 12) and acrylamide (6 sec., Figure 13) using the continuous method. 

Polyethylene has been grafted with acrylic acid, 2-hydroxyethyl methacrylate//V,/V-dimethylacrylamide, or methacrylic acid//V,/V-dimethylacrylamide to yield supports (e.g. Figure 2.10) suitable for the synthesis of peptides [2,222-224] and other compounds [216,225,226]. A similar support, also suitable for the synthesis of peptides, is polypropylene grafted with hydroxypropyl acrylate [227]. These supports can be used as membranes or as crown-shaped pinheads (Multipin 2-4 mm diameter) with loadings of 1.2-2.2 pmol per crown. 

Hydroxybutyric acid-hydroxyvaleric acid copolymer membranes were treated with ozone and grafted with acrylic acid. The membranes were further grafted with chitosan or chitooligosaccharide via esterification and immobilised with hyalmonic acid. Antibacterial activities were investigated. Surface properties were characterised using a water contact angle goniometer. 26 refs. 

Not surprizingly, in view of the preceding preference for hydrophobic surfaces, PAn can also be deposited by the in situ method on supports such as low-density polyethylene (LDPE).35 Modification of the LDPE surface by grafting with acrylic acid promotes the growth and adhesion of the PAn films. Conducting PAn coating may be similarly deposited on PVC and PMMA surfaces through chemical oxidative polymerization.36... 

PARA with PE-MA, or PP and hydrazine [Yoshihara, 1990]. Blends of copolyphthalamide (PPA) with PP were compatibilized using either PP-MA [Paschke et a/., 1993, 1994] orPP-grafted with acrylic acid [Brooks et al, 1993, 1994]. 

Graft polymers containing the carboxyl ligand have also been prepared. For example, acrylic acid can be grafted to an inert support such as polypropylene or polyethylene by two main pathways. In one path the graft polymerization is initiated by radical initiators. For instance, polypropylene is suspended in H2O and grafted with acrylic acid in the presence of water-insoluble radical initiators in water-miscible solvents (14). The other path involves the grafting of acrylic acid to polyethylene by gas phase polymerization (15). 

Electron beam irradiation is another commonly used method to modify the surface hydrophlicity of microporous polyolefin membranes. In a typical process, a microporous PP membrane was grafted with acrylic acid and diethylene glycol-dimethacrylate (DEGDM) (Nasef and Hegazy, 2004) monomers using electron beam irradiation to create a hydrophilic surface. The modified membranes showed enhanced electrolyte uptake, ionic conductivity, and cycle life as compared with unmodified PP membranes. Glycidyl methacrylate (GMA) and methyl methacrylate (MMA) (Kim and lim, 2010) have also been... 

After the discovery of carbon nanotube (CNT) by Ijima (1991), extensive works have been devoted in extracting the optimum properties of the CNTs. Wu (2009) studied PTT/MWCNT composites. The hydroxyl functionalized (MW-CNT-OH) behaves as anchoring sites for the PTT grafted with acrylic acid (PTT-g-AA) (compare to Scheme 1). The functionalization of MWCNT improves the compatibility and dispersibility of the MWCNT in the matrix of PTT. The thermal and mechanical properties (compare to Tables 14 and 15) show a dramatic increase leading to the conclusion that functionalized MWCNT can be used for preparing high performance PTT nanocomposites. 

Reactive grafting of polyolefins, polyethylenes (PE), or polypropylenes (PP) was disclosed. The extruder was modified, allowing to feed polymer, grafting monomer and peroxide. As an example, PP was grafted with acrylic acid... 

Applications. Poly(ethylene oxides) are readily grafted with acrylic acid to give partially biodegradable detergent pol5miers (208-210). Grafts onto other substrates include poly(vinyl alcohol) (211), water-soluble maleic anhydride copolymers (212), polycaprolactone (213), and onto emnlsion polymers of acrylates and methacrylates (214). 

Gums Grafted with Acrylic Acid or Its Derivatives... 

Guar gum grafted with acrylic acid, methacrylic acid, 2-hydroxyethyl methacrylate and 2-hydroxypropyl methacrylate 1-tyrosine and 3,4-dihydroxy phenylalanine (1-DOPA) as the model pro-drugs Hydrogel The % cumulative release of L-tyrosine and L-DOPA was the maximum from the AGG-g-poly (methacrylic acid) and AGG-g-poly (AAc), respectively, in both pH 2.2 and 7.4 [124]... 

Acrylic and methacrylic acids have been grafted to polypropylene films [73] and polyester (terylene) fibers [74]. Treatment of the substrate with ferrous ions seems to favor the grafting with acrylic acid while cupric ions favor grafting with methacrylic acid. 

Polyurethane grafts with acrylic acid Plasma modification of surface 31... 

Huang, F., et al.. Dynamic Wettability and Contact Angles of Poly (Vinylidene Fluoride) Nanofiber Membranes Grafted with Acrylic Acid. Express Polymer Letters, 2010,4(9), 551-558. 

Surface treatment of CaCOj can change its nucleating activity in iPP. In Reference [134] iPP composites with nano-CaCOs were modified with iPP grafted with acrylic acid (PP-g-AA). of iPP in the composites increased with increasing nano-CaCOs content, and it was further increased by the addition of PP-g-AA. Recently, composites of iPP with 1 wt% and 3 wt% of nanosized calcium carbonate, both calcite and aragonite, coated either with PP-g-MA or fatty acids were... 

Huang, F.L., Wang, Q.Q., Wei, Q.R, Gao, W.D., Shou, H.Y, Jiang, S.D., 2010, Dynamic wettability and contact angles of poly(vinylidene fluoride) nanofiber membranes grafted with acrylic acid. Express Polym Letters 4(9) 557-558. 

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