Grafting monomers crosslinkers

Other important factors include monomer sequence distribution, distribution of graft and crosslink sites along the chains, the occurrence of branching per se, and the general phenomena of side reactions. In addition, stirring rate, the detailed post-reaction "workup procedure, the temperature history, subsequent processing and fabrication conditions, etc. must be considered since these have major effects on the nature of the product. 

Acrylic acid or methacrylic acid-starch graft copolymers were proposed as floc-culants for bauxites,2714,3095 agents for sizing cotton,3096-3098 tanning materials,3099 paper additives,3100 and also for sanitary napkins, diapers, tampons, and sick-bed sheets.3101-3104 Particular attention was devoted to the use of vinyl monomer grafted onto crosslinked starch.3105 Other applications include antiflammatory... 

In addition, allyl methacrylate is often added to a latex formulation as a crosslinking/grafting monomer [52] especially in the case of core-shell latexes. This monomer is often used to promote adhesion between various polymeric layers, especially in multilayered composite latex particles, which are often used as impact modifiers [53]. 

An interpenetrating polymer network (IPN) is defined as a combination of two crosslinked polymers, at least one of which has been synthesised [98] and/or crosslinked in the immediate presence of the other. From the topological point of view, IPNs are closely related to pol)nner blends and to block, graft and crosslinked copolymers. From the synthesis point of view, IPNs can be classified, broadly, into two general types (a) sequential IPNs where a polymer network is formed which is then swollen by the monomer, plus a crosslinking agent and an activator, which is then polymerised in situ to form the second network and (b) simultaneous IPNs (SIPN) where the components necessary to form both networks are mixed and polymerised, at the same time, by non-competing mechanisms. If one of the two polymers is linear (uncrosslinked), a semi-IPN results. A homo-IPN results if both the network polymers are identical in chemical composition [98]. 

Miniemulsion polymerization enables to incorporate water-insoluble materials such as resins, organic pigments, polymers, etc into the polymer matrix. The additive seed allows to control the particle number and particle size during the production process. Furthermore, miniemulsion polymerizations and copolymerizations carried out with acrylic and methacrylic monomers in the presence of unsaturated alkyd resins lead to the production of stable hybrid latex particles containing grafted and crosslinked alkyd resin/acrylic products as coating polymer [114]. In the reaction, the multifunctional resin acts as a hydrophobe as well as the costabilizer of the miniemulsion. 

The influence of crosslinker type (DVB, BVPE, TAG) and concentration on the ex situ stability of the resulting membranes was studied by Chen et al. (2006a) using 50-pm ETFE as the base film and MeSt as the primary grafting monomer... 

Fig. 9 Ex situ chemical stability of (m,/7-methylstyrene + crosslinker) grafted and sulfonated membranes in 3% solution at 50°C as a function of the crosslinker content (vol%) in the grafting monomer mixture. Durability time is associated with the onset of significant (more than approximately 10%) membrane weight loss. XL crosslinker (data reprinted from Chen et al. 2006a. Reprinted with the permission of John Wiley Sons, Inc.)...

A polymer, by conventional definition, is a macromolecule made up of multiple equivalents of one or more monomers linked together by covalent bonds (e.g., carbon-carbon, amide, ester, or ether bonds) [1]. These conventional polymers come in many configurations for example, linear homopolymers, linear copolymers, block copolymers, crosslinked polymers, dendritic polymers, and others. The most common architecture for polymers is based on linear chains that may have other attached chains (branched, grafted, or crosslinked) that is, they are one-dimensional molecules. A few examples have been claimed as two-dimensional sheet polymers. ... 

If (P ) is terminated by a chain transfer to a solvent or a monomer, a graft copolymer is formed, or, if the termination is from a combination, a crosslinked network polymer is formed. If the pre-existing polymer (B) contains an end group that itself is photosensitive (or can produce a radical by interacting with photoinitiator) and in the presence of a vinyl monomer (A), block copolymer of type AB can be produced if the photosensitive group is on one end of the polymeric chain. Type ABA block copolymer can be produced if the polymer chain (B) contains a photosensitive group on both ends. 

When these polymers are subjected to light of A = 365 nm in bulk vinyl monomer, (MMA or styrene) grafted or extensive crosslinking polymers were produced. The photografting or photocrosslinking occurs through the macro-radicals photochemically generated on the backbone of the polymer ... 

The epoxy-acrylic resin referred to above is a graft copolymer prepared by the polymerisation of acrylic monomers in the presence of the epoxy resin in such a way that grafting of the acrylic onto the epoxy takes place. Water dispersibility is achieved by neutralising carboxyl groups in the acrylic polymer chain with ammonia or amine. Amino or phenolic resins are used as crosslinkers. Alternatively, solvent-borne epoxy-amino or epoxy-phenolic lacquers can be used. 

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