Tris-nonylphenyl phosphite

Peroxide-decomposing antioxidants destroy hydroperoxides, the sources of free radicals in polymers. Phosphites and thioesters such as tris(nonylphenyl) phosphite, distearyl pentaerythritol diphosphite, and dialkyl thiodipropionates are examples of peroxide-decomposing antioxidants. 

Because nitrile rubber is an unsaturated copolymer it is sensitive to oxidative attack and addition of an antioxidant is necessary. The most common practice is to add an emulsion or dispersion of antioxidant or stabilizer to the latex before coagulation. This is sometimes done batchwise to the latex in the blend tank, and sometimes is added continuously to the latex as it is pumped toward further processing. PhenoHc, amine, and organic phosphite materials are used. Examples are di-Z fZ-butylcatechol, octylated diphenylamine, and tris(nonylphenyl) phosphite [26523-78-4]. All are meant to protect the product from oxidation during drying at elevated temperature and during storage until final use. Most mbber processors add additional antioxidant to their compounds when the NBR is mixed with fillers and curatives in order to extend the life of the final mbber part. 

Applications Extraction is typically accomplished by refluxing the polymer in an appropriate solvent for l-48h [84,199]. In many cases, ultrasonic exposure reduces the extraction time [90,200], According to Table 3.5 there are several reports of US extraction from polymers. Ultrasonic extraction has been used for HDPE/(BHT, Irganox antioxidants, Isonox, Cyasorb, Am 340, MD 1024, Irgafos 168) [56], LDPE/Chimassorb 81 [201], SBR/tri(nonylphenyl) phosphite [200], HDPE/(Tinuvin 770, Chimassorb 944) [114], etc. Nielson [90] compared the recoveries obtained for a variety of analytes from PP, LDPE and HDPE with Soxhlet, ultrasonic bath and microwave oven. For all samples, the ultrasonic extraction could be achieved within 1 h. For LDPE and PP most compounds (except Irganox 1010) were extracted within 10 min. Further experiments by Nielson [56] on extraction from HDPE confirmed these results. Where phosphite antioxidants (such as Irgafos 168) are present the use of the solvent mixture DCM-cyclohexane was preferred as it prevented hydrolysis of the phosphite by extraction solvents such as alcohols [56]. Similarly, phosphite esters also undergo hydrolysis... 

Brandt [200] has extracted tri(nonylphenyl) phosphite (TNPP) from a styrene-butadiene polymer using iso-octane. Brown [211] has reported US extraction of acrylic acid monomer from polyacrylates. Ultrasonication was also shown to be a fast and efficient extraction method for organophosphate ester flame retardants and plasticisers [212]. Greenpeace [213] has recently reported the concentration of phthalate esters in 72 toys (mostly made in China) using shaking and sonication extraction methods. Extraction and analytical procedures were carefully quality controlled. QC procedures and acceptance criteria were based on USEPA method 606 for the analysis of phthalates in water samples [214]. Extraction efficiency was tested by spiking blank matrix and by standard addition to phthalate-containing samples. For removal of fatty acids from the surface of EVA pellets a lmin ultrasonic bath treatment in isopropanol is sufficient [215]. It has been noticed that the experimental ultrasonic extraction conditions are often ill defined and do not allow independent verification. 

TBBA, TBBP-A Tetrabromobisphenol-A TNPP Tris (nonylphenyl) phosphite... 

Polyvinylchloride (PVC). Kim et al. (H) analyzed the volatiles of polyvinylchloride (PVC), one of the most versatile packaging materials. The major precursors for the formation of the volatile compounds were considered to be PVC polymer, bis-(2-ethylhexyl) adipate (DOA), bis-2-(ethyl hexyl) phthalate (DOP) and tris-nonylphenyl phosphite and epoxidized soybean oil. 

Therefore, additional heat aging tests were conducted to investigate the possibility that hydroquinone-derived phenolic groups might function differently from the monohydric phenols and somehow contribute to the high activity of the phenolic-phosphite systems. Two substituted hydro-quinones, two polymeric phenolic phosphites based on those hydro-quinones, and combinations of the hydroquinones with triphenyl phosphite and tris(nonylphenyl) phosphite were evaluated in the oven-aging test again 0.4% DLTDP was included in the formulations. 

Processing Stability. The ability of tris (nonylphenyl) phosphite to prevent degradation of polypropylene during processing is believed related to its efficiency to decompose peroxides into non-active species. In a similar way, the phosphite groups on the polymeric phosphites may also be capable of decomposing peroxides (see top of p. 217). 

Three separate processing stability tests were run, and comparisons were made between (1) tris (nonylphenyl) phosphite and a PPP, (2) two commercial resins, and unstabilized resin containing the synergistic DLTDP-PPP combination, and (3) DLTDP alone, a PPP alone, a combination of the two, and unstabilized resin. 

Repeated Extrusions. 0.25% Tris(nonylphenyl) phosphite and 0.25% polymeric phenolic phosphite were added to unstabilized polypropylene, and the resins were run through the laboratory extruder four times. The barrel temperature was 450°F., and the stock temperature of the extrudate was approximately 500°F. Melt flow rate of samples taken after each pass was measured according to ASTM 1238-62T. 

The results are shown in Figure 1. PPP was comparable with the tris(nonylphenyl) phosphite in preventing process degradation, although it wasn t quite as effective. The unstabilized base resin, however, became soupy, discolored, and had a melt flow rate of more than 10 after four passes. Aryl phosphite and the PPP gave considerably less discoloration, and melt flow readings of 3.9 and 4.7, respectively, after four passes through the extruder. 

The specialists in rubber additives are distinctly different from the specialists in additives for plastics, even though the same products are sometimes used in both industries blowing agents (azodicarboamide), phenol antioxidants (BHT, 2246), phosphites (tris-nonylphenyl phosphite). In the first place, additives for elastomers, unlike those which might come into contact with foodstuffs, do not require official approval, which... 

Tris nonylphenyl phosphite tris(mono-nonylphenyl) phosphite nonylphenyl phosphite (3 1)... 

A mixture of monomers and TDM is added with mixing to the polybutadiene substrate for 5 hrs in the presence of the initiator system and the emulsifier. After polymerization, latexes were stabilized by adding 2,6-di-ter -butyl-p-cresol (DBPC) or tri(nonylphenyl) phosphite (TNPP) as antioxidants. They were then coagulated with a calcium chloride solution and finally dried at 50°C for 15 hrs. 

Phosphites tris(nonylphenyl)phosphite Irgaphos TNPP 26523-78-4... 

Typical processing stabilizers for polypropylene and butylated hydroxy-toluene (BHT) as the primary antioxidant and phosphates and phosphonates as secondary antioxidants. Examples of the latter that are commonly used are tetrakis-(2,4-di-terr-butyl-phenyl)-4-4 -bisphenylylenediphosphonite, distearyl-pentaerythrityl-diphosphonite, tris-(nonylphenyl)-phosphite, tris-(2,4-di-teft-butyl-phenyl)-phosphite and bis(2,4-di-ferr-butyl-phenyl)- pentaerythrityl-diphosphite. In commercial polypropylenes, phosphorous compounds are always used together with a sterically hindered phenol. The compounds are commonly added in concentrations between 0.05 and 0.25%. 

The performance of a primary antioxidant can be improved by the use of a secondary antioxidant. Secondary antioxidants or peroxide decomposers do not act as radical scavengers but undergo redox reactions with hydroperoxides to form nonradical stable products (Fig. 2). This class of antioxidants (Table 3) includes phosphites such as tris(nonylphenyl)phosphite (PS-1) and thiosynergists or thioesters such as dilauryl... 

Among recent developments, there is the stabiliser of high-purity tris-nonylphenyl phosphite, with 0.1% residual nonyl phenol, which is FDA-approved for food-contact (and medical) applications. 

Tris nonylphenyl phosphite is one of the oldest and most often used phosphite stabilizers for polymeric materials. In liquid form, it is economical to use even at over twice the loading of alternative dry phosphites, and its hquid form has advantages in handling and metering. It is used in LLDPE bags and food packaging and HOPE blow-molded dmms and box wrapping film [3-5, 3-6]. 

Trilauryl phosphite Tris-nonylphenyl phosphite (TNPP)... 

Pentaerythrltyl tetrakis [3-(3,5 -dl-t-butyl-4-hydroxyphenyl) propionate] Poly (dipropyleneglycol) phenyl phosphite Seenox DL Seenox DS Thiodiethybne bis (3,5-di-t-butyl-4-hydroxy) hydrocinnamate, Tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate, Tris (nonylphenyl) phosphite, Weston TDP Weston TNPP antioxidant, PU polyols Naugard 445 antioxidant, PVB BNX MD-1024 antioxidant, PVC... 

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