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Dibasic lead stearate

By far the most common lead salt used for PVC stabilization is tribasic lead sulfate. It can be found either alone or combined with another lead salt in almost every lead-stabilized PVC formulation. Many of the combinations are actually coprecipitated hybrid products, ie, basic lead sulfophthalates. Dibasic lead stearate and lead stearate are generally used as costabilizers combined with other primary lead salts, particularly in rigid PVC formulations where they contribute lubrication properties dibasic lead stearate provides internal lubrication and lead stearate is a good external lubricant. Basic lead carbonate is slowly being replaced by tribasic lead sulfate in most appHcations due the relatively low heat stabiHty of the carbonate salt which releases CO2 at about 180°C during PVC processing. [Pg.551]

Rigid Applications. The use of the lead stabilizers is very limited in the United States but, they are stiU used in several rigid PVC appHcations in Europe and Asia. The highest use of lead stabilizers in rigid PVC is for pipe and conduit appHcations. Tribasic lead sulfate is the primary heat stabilizer with lead stearates included to provide lubrication. The lead products are typically fully formulated, usually including lubricants and pigments for pipe extmsion appHcations. These lead one-packs, when used at about 1.8—2.5 phr, provide all of the stabilizer and lubrication needed to process the polymer. A lead one-pack contains tribasic lead sulfate, dibasic lead stearate calcium stearate, polyethylene wax, paraffin wax, ester wax, and pigments. [Pg.552]

Normal and dibasic lead stearate have a stabilising effect but their main uses are as lubricants (see section 12.5.4). Lead silicate is sometimes used in leathercloth formulations but is today of little importance. Other lead compounds now of negligible importance are coprecipitated lead orthosilicates and lead salicylate. [Pg.328]

In Britain calcium stearate has been most commonly used with nontransparent products and stearic acid with transparent compounds. In the United States normal lead stearate, which melts during processing and lubricates like wax, is commonly employed. Dibasic lead stearate, which does not melt, lubricates like graphite and improves flow properties, is also used. [Pg.337]

IR and NMR spectra of basic lead carboxylates used as heat stabilisers for halogenated polymers, e.g. PVC, indicated that these salts were not complexes, or double compounds of lead oxide, as suggested in most textbooks, but unique compounds of interesting structure. Stabilisers studied included monobasic lead phthalate, tribasic lead maleate, tetrabasic lead fumarate, dibasic lead phthalate and dibasic lead stearate. Lead stabilisers probably functioned in these polymers by converting hydrogen chloride to water, interfering with acid catalysis of the elimination reaction. 6 refs. [Pg.141]

Dried chlorella powder and PVC (n llOO) were used. As the stabilizer some chemical additives were used. These chemicals were dibasic lead stearate (DEL), tribasic lead sulfate (TC),cadmium/barium/lead fatty acids complex (U500), barium/zinc fatty acids complex (PSE) and paraffin. Usually we used the mixture of 20% chlorella and PVC with TC 1.5%, DEL 0.5%, 1 500 0.5% of PVC respectively. [Pg.479]

Lubricant Prevent adhesion of polymer to processing equipment Sweats out due to low compatibility with polymer Calcium stearate, normal and dibasic lead stearate... [Pg.194]

Lead carbonate basic Lead 2-ethylhexoate Lead phthalate, dibasic Lead stearate, dibasic Lead sulfate, basic Magnesium/aluminum/hydroxide/carbonate Methyltin tris (isooctylthioglycollate) Methyltin tris (2-mercaptoethyl oleate) p-Nonyl phenol (n-Octyl) tin S,S, S" tris (isooctyl mercaptoacetate) 2-Phenyl indole Thiodiglycol di-P-aminocrotonate Tris (nonyiphenyi) phosphite Tris (tridecyl) phosphite Zinc laurate Zinc stearate... [Pg.5738]

Lead Tribasic lead sulfate Dibasic lead phalate Dibasic lead stearate Wire Cable General Flexible Products... [Pg.365]

Dibasic lead stearate n. 2PbO Pb(OOCCi7 H35)2. a good heat stabilizer with lubricating properties. [Pg.275]

Fig. 9.6. Relation between heating time at 180°C in the air and the quantity of HCl evolved from PVC stabilized by dibasic lead stearate [65]. Curve 1 sheet obtained by homogenization in a twin-roll mixer curve 2 homogenized powder in a turbomixer. Fig. 9.6. Relation between heating time at 180°C in the air and the quantity of HCl evolved from PVC stabilized by dibasic lead stearate [65]. Curve 1 sheet obtained by homogenization in a twin-roll mixer curve 2 homogenized powder in a turbomixer.
Tlrixylyl phosphate Dibasic lead stearate Caldum stearate... [Pg.21]

The presence of lubricants and stabilizers notably influences resistance of PVC mixtures. Dibasic lead stearate and a fatty acid-free Ba/Cd stabilizer act as growth inhibitors [972],... [Pg.870]

Vinyl chloride/vinyl acetate copolymer (VC/VA, 87 13) Dibasic lead stearate (lubricant/stabilizer)... [Pg.132]

See other pages where Dibasic lead stearate is mentioned: [Pg.297]    [Pg.551]    [Pg.551]    [Pg.297]    [Pg.128]    [Pg.58]    [Pg.171]    [Pg.215]    [Pg.321]    [Pg.329]    [Pg.330]    [Pg.334]    [Pg.375]    [Pg.129]    [Pg.453]    [Pg.364]    [Pg.306]    [Pg.3666]    [Pg.152]    [Pg.155]    [Pg.301]    [Pg.869]   
See also in sourсe #XX -- [ Pg.328 , Pg.337 ]

See also in sourсe #XX -- [ Pg.328 , Pg.337 ]

See also in sourсe #XX -- [ Pg.321 , Pg.329 , Pg.330 ]

See also in sourсe #XX -- [ Pg.364 ]

See also in sourсe #XX -- [ Pg.328 , Pg.337 ]



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Dibasic lead

Lead stearate

Stearate

Stearates

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