The combined plasticization of jute and tung oil anhydride for jute fiber reinforced poly(lactic acid) composites

In this work, novel plasticizing biodegradable poly (lactic acid) (PLA) composites were prepared by melt blending of jute and tung oil anhydride (TOA), and the physical and mechanical properties of PLA/jute/TOA composites were tested and characterized. The impact strength of PLA/jute/TOA composites significantly increases with increasing the content of TOA. The SEM images of fracture surface of PLA/jute/TOA composites become rough after the incorporation of TOA. In addition, TOA changes the crystallization temperature and decomposition process of PLA/jute/TOA composites. With increasing the amount of TOA, the value of storage modulus (E′) of PLA/jute/TOA composites gradually increases. The complex viscosity (η*) values for all samples reduce obviously with increasing the frequency, which means that the pure PLA and PLA/jute/TOA composites is typical pseudoplastic fluid. This is attributed to the formation of crosslinking, which restricts the deformation of the composites.

Iodine value of tung biodiesel fuel using Wijs method is significantly lower than calculated value

The tung tree (Vernicia fordii) is a non-edible oil plant native to southern China and was introduced in Japan in the nineteenth century. The tree produces tung oil, which is composed of approximately 80% α-eleostearic acid (9c, 11t, 13t-octadecatrienoic acid), 7% linoleic acid, and 6% oleic acid. Tung oil may be a non-edible source of biodiesel fuel (BDF) production. The iodine value (IV) is one of parameters to guarantee BDF quality, and the most common method for the determination of IV is the Wijs method. The IV can be calculated from the average molecular weight and the number of double bonds from the GC–MS data. In this study, the IVs of olive, castor, soybean, linseed, and perilla BDF using the Wijs method were found to be almost the same as the calculated IV. On the other hand, the IV of tung BDF by the Wijs method indicated a significantly lower value than that of the calculated value. To determine the cause of this discrepancy, the samples before and after halogenation using the Wijs method, were analyzed by 1H NMR. The conjugated double bond signals did not disappear, and a broad double bond signal remained in the tung BDF spectrum after halogenation. These results demonstrated that iodine, with a large atomic radius, could not react completely with the three conjugated double bonds in α-eleostearic acid. Therefore, the IV of tung BDF was significantly lower than the calculated value.

Multianalytical Assessment of Armour Paints—The Ageing Characteristics of Historic Drying Oil Varnish Paints for Protection of Steel and Iron Surfaces in Sweden

The characteristics of armour paints, historically used to protect ferrous industrial heritage, are explored. Amour paints contain lamellar and highly reflexive pigments of micaceous iron oxide (MIO) and metallic, leafing aluminium, bound in linseed oil and linseed oil–tung oil mixtures, on an inhibitive and soap-forming linseed oil primer (red lead). It is the first study of the binding media used for historical armour paints and investigates the chemical and physical ageing of armour paints using a multianalytical approach. Naturally aged examples are compared to accelerated aged replica armour paint, and to historical paints. The ageing and degradation reactions are assessed by complementary GC–MS and FTIR, together with measurements of wettability, hardness and surface colour. The historical paint formulations include linseed oils and alkyd binders. The results confirm that the leafing effect of aluminium pigments results in only a small concentration of binder at the surface: the paints studied reflect light and form a strong chemical and physical barrier. Linseed oils and tung oil mixtures have been proven to be suitable for the production of armour paints, but the evaluation of ageing and assessment of physical changes will require further investigation.