Polymeric nucleating agent

Nucleated polypropylene composition for containers includes a polymeric nucleating agent obtainable by polymerizing vinylcycloatkane monomers or vit lalkane monomers. ... 

These newer PET formulations utilize not only a nucleating agent, but also a plasticizing agent [3-9], The crystallization rate of polymeric materials can be broken down into two different regions, i.e. nucleation-controlled and diffusion-controlled (Figure 15.3). In the injection molding process, hot polymer is injected... 

Nucleation agents are substances that are able to initiate and control cell formation and growth. They are purposely incorporated into the polymeric structure. At their location, the blowing agent (pentane) preferably evaporates when the EPS beads are exposed to saturated steam. However, unwanted... 

Commercial polyolefins often contain additives such as colorants, flame retardants, antioxidants, light stabilizers, nucleating agents, antistatic agents, lubricants (microcrystalline waxes, hydrocarbon waxes, stearic acid, and metal stearates), and so on. These additives aid the processing and fabrication of products from polyolefins. Detailed treatments about specific polyolefins, polymerization systems/ mechanism/processes, structures, properties, processing, and applications may be found in References 2-9. 

Also, Amash and Zugenmaier [38] observed an increase in the crystallization temperature of polymeric matrix with the addition of cellulose fibers and MAPP, used as a compatibilizing agent. The DSC results clearly show that the addition of small amounts of cellulose fibers to PP increases the crystallization temperature of the polymer matrix. The effects observed can be explained by the assumption that the cellulose fibers act as efficient nucleating agents for the crystallization of PP. 

Nylon, nucleated n. A nylon polymerized in the presence of a nucleating agent, e.g., about 0.1% of finely dispersed silica, which promotes the growth of spherulites and controls their number, type, and size. Nucleated nylons have higher tensile strength, flexural modulus, abrasion, resistance, and hardness, but lower impact strength and elongation than their unnucleated counterparts. 

Consequently, dispersed entities (particles, nanostructures, etc) can act as effective nucleation agents when they provide a potential nucleation site with a lower energy barrier than the surrounding polymeric matrix. 

Polymerized dispersion is still another technique to increase stability of the nucleating agent dispersion." Stearic acid and stearate lanthanirm complex were polymerized into isotactic polypropylene via in situ polymerization." The content of P-phase in nucleated PP can reach as high as 88.7% with only 0.135 wt% of nucleating agent."... 

An extraded air cooled blown film has been produced from polypropylene with nucleating agent based polymeric amide. ... 

A high boiling hydrofluoroethers were used as nucleating agents in the production of a polymeric foam, in particular in the production of polyurethane foams and phenolic... 

A polyisocyanurate foam is prepared by polymerizing a polyol compoimd with an isocyanate compound. A liquid silane compoimd is used as a nucleating agent for foam formation in the polymerization. The polyisocyanurate foam has foamed cells whose sizes are relatively small compared to the size of the foamed cells of the conventional... 

Polymeric compositions contain clay nucleating agents. The clays are preferably sepiolite, palygorskite/attapulgite, or their combinations. The resulting products llud particular application as insulation and packaging materials. ... 

Rotomolding additives include nucleating agents, such as, inoiganic substances such as talcum, metal oxides such as titanium dioxide or magnesium oxide, phosphates, carbonates or sulfates of, preferably, alkaline earth metals organic compounds such as mono- or polycarbojQ lic acids and their salts, e g., 4-tert-butylbenzoic add, adipic acid, diphenylacetic acid, sodium succinate or sodium benzoate polymeric compounds such as ionic copolymers (ionomers). ... 

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