Blowing agent activator

EB radiation-cured PVC film surface induces a big improvement in tensile strength and excellent printing ink adhesion and adhesive receptance [302]. PVC foams containing plasticizers, thermally activated blowing agents, cross-linkers, and heat stabilizers have been manufactured by EB radiation technology [303]. 

Pastes used as accelerators, activators, blowing agents, dessicants, flame retarders, vulcanizers. 

Ken-React QB 012 Ken-React QB 321 Ken-React QB 521 activator, blowing agents coatings... 

Tetraacetyl ethylenediamine activator, bleach heavy-duty detergents Tetraacetyl ethylenediamine activator, bleach machine dishwash Tetraacetyl ethylenediamine activator, bleach stain removers Tetraacetyl ethylenediamine activator, bleach toothpaste Tetraacetyl ethylenediamine activator, blowing agents Isopropyl titanium triisostearate Tetraisopropyl di (dioctylphosphito) titanate activator, butyl rubber Poly-p-dinitrosobenzene activator, castings... 

Microspheres ml-kr9- sfirs (1894) n. Tiny, hollow spheres of glass or plastic used as fillers to impart low density to plastics, such plastics being known as syntactic foams. Plastics used to make microspheres include phenohc, epoxy and a co-polymer of vinylidene chloride and acrylonitrile. The last contains a heat-activated blowing agent that expands the spheres either before their incorporation into a matrix polymer or afterward. The co-polymer spheres impart better mechanical properties to the matrix than do the glass or epoxy microspheres. 

Figure 5-58. Lightweight, durable covers for pickup track beds are made of structural foam moldings of Prevex resin with a foam concentrate called Spectratech FM1776L, firom Quantum Chemical Corp. This chemically activated blowing agent does not attack the injection-molding barrel and screw or the mold s surfaces. Furthermore, since there is very little postblow with the blowing agent, the parts can be painted within four hours of being molded.

Chemical Stabilization. The chemistry of the system determines both the rate at which the polymer phase is formed and the rate at which it changes from a viscous fluid to a dimensionally stable cross-linked polymer phase. It also governs the rate at which the blowing agent is activated, whether it is due to temperature rise or to insolubilization in the Hquid phase. 

A most widely used decomposable chemical blowing agent is azodicarbonamide. Its decomposition temperature and rate of evolution of gaseous components are greatly influenced by the stabilizers containing zinc. Lead and cadmium are considered moderate activators for, -oxybis benzenesulfonyl hydrazide (OBSH). OBSH can also be used as a blowing agent for PVC foams. 

Tetrazole, 5-phenoxy-l -phenyl-mass spectra, 5, 801 photolysis, 5, 811 Tetrazole, 1-phenyl-deuterium-hydrogen exchange, 5, 806 mercuration, 5, 59 NMR, 5, 798 tautomerism, 5, 804 UV spectra, 5, 798 Tetrazole, 2-phenyl-NMR, 5, 798 tautomerism, 5, 804 UV spectra, 5, 798 Tetrazole, 5-phenyl-alkylation, 5, 818 anti-inflammatory activity, 5, 835 blowing agent, 1, 410 reactions... 

NaHC03, a blowing agent, often used with a weak acid to activate its decomposition to produce C02 Sodium Bisulphite... 

ADCA has been marketed in blends with a variety of activators. These systems can be used to give better cell uniformity, better uniformity of colour and more uniform product hardness. The different activators also influence the temperature at which the effective decomposition of the blowing agent takes place. 

The next step is the incorporation of various additives—compounding. Typical additives include fillers, processing aids, activators, age resistors, sulfur, antioxidants, and antiozone compounds, extenders, plasticizers, blowing agents, pigments, and accelerators. 

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