BHT antioxidant

Sample Preparation. The UHMWPE used in this study was a HiFax 1900 (Himont, Inc.) with an average molecular weight of 2-8 x 10. The UHMWPE was added to paraffin oil to concentrations from 2 to 5% w/w. To avoid polymer degradation at high temperatures, the polymer was stabilized with approximately 0.5% of BHT antioxidant. The mixture was stirred at 150 C. A solution was obtained that was clear until it was cooled to about 120 C when it became opaque and transformed into a gel-like or pseudo-gel. 

BHT Antioxidant (0.01% w/v) Prevents oxidation of fats and oils and enhance color stability. Heating with catalytic amounts of acids causes rapid decomposition... 

Butylated hydroxyanisole (BHA), antioxidant, 556-557 Butylated hydroxytoluene (BHT), antioxidant, 556-558... 

Till, D.E., Ehntholt, D.J.. Reid, R.C., Schwartz, P.S., Sidman, K.R., Schwope, A.D., Whelan, R.H., 1982, Migration of BHT antioxidant from high density polyethylene to foods and food simulants. Industrial Engineering hemistry, Product Research and Developmental (1) 106-113. 

Table 1. Number average molecular weights (M ) of PVC as a function of reaction time in the absence and presence of BHT antioxidant during thermo-oxidative degradation (DOP, O2,200 C).

In an excellent review of variables influencing the analysis of carotenoids by HPLC, Scott [768] noted that some parameters had adverse effects on the system, First, stainless steel frits seemed to lead to lowered responses for 8-cryptoxanthin and a- and / -carotene. Replacement of the frits with metal-free frits increased responses, but the replacement of stainless steel column tubing and injector tubing did not increase response. This is most likely a result of the large disparity in contact surface areas between the frits and the tubing. Storage of lycopene samples in 0.1% BHT (antioxidant)-preserved chloroform vs. chloroform without BHT showed considerably less degradation with time. The same results were found for BHT-preserved THF vs. unpreserved THF. Optimization of extraction procedures is also addressed in this paper. 

Franich and co-workers [5] described two simple methods using internal standards for the quantitative analysis of 2,6-di- er -butyl-4-methylphenol (butylated hydroxy toluene, BHT) antioxidant in samples of solvent-formulated liquid adhesive and in cured polychloroprene adhesive films. Because only very small samples of cured adhesive could be taken from articles or components without substantially detracting from the product, the methods were developed to use minimal quantities of cured adhesive. The Py-GC method required... 

Keen and co-workers [20] used EGA to monitor the evolution of additives from rubber and polymers in order to evaluate the effectiveness of encapsulated BHT antioxidant from polyisoprene. The technique involves the coupling of a thermogravimetry mass spectrometry with oxidative DSC. 

Recently, Medeiros et al. [55] proposed a new procedure for simultaneous quantification of BHA and BHT antioxidants using multiple pulse amperometry (MPA) with FIA in food samples (commercial mayonnaise). Determination of these phenolic antioxidants was performed with a cathodically pretreated boron-doped diamond detector and a dual-potential waveform was used which first promoted the only the oxidation of BHA and second of... 

Keywords foam, BHT, antioxidant, phenolic, discoloration, phosphite, degradation. 

MSPD sample (2 g) was blended with BHT (antioxidant) and C18 sorbent (maize flour) or diatomaceous earth and Na2S04 (kiwi fruits). A syringelike glass tube was filled with the diversion (Teflon frits above and below the sorbent—food matrix bed). Elution in sequence with methanol, isopropanol, and hexane. The concentrated pooled extracts (500 til), diluted to 1 ml with isopropanokexane (50 50, v/v), centrifuged, and injected into the LC—MS/MS system... 

Sample preparation Serum. Extract one volume (20-100 pL) serum with three volumes isopropanohdichloromethane 2 1 containing about 6 nM IS and 1 mM butylated hydroxytoluene (BHT, antioxidant), add glacial acetic acid (1 pL/20 pL serum). Vortex for 30 s, centrifuge for 1 min, inject a 20-70 pL aliquot of the supernatant. Tissue, food. Homogenize 100-200 mg human or rat liver, 200 mg-2 g other tissues, or 2-5 g pulp of fruits and fresh vegetables with 3-5 mL isopropanohdichloromethane 2 1, make up to 10 mL with isopropanohdichloromethane 2 1. Vortex for 1 min, keep under argon... 

Chem. Descrip. Lanolin alcohol, mineral oil, and octyidodecanol with 150 ppm BHT (antioxidant)... 

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