Plastisol foaming process. Decomposition of the foaming agent, polymer behavior in the corresponding temperature range and resulting foam properties

Abstract

is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. The decomposition of azodicarbonamide, used as foaming agent in PVC-plasticizer (1/1) plastisols was studied by DSC. Nineteen different plasticizers, all belonging to the ester family, two being polymeric (polyadipates), were compared. The temperature of maximum decomposition rate (in anisothermal regime at 5 K min 21 scanning rate), ranges between 434 and 452 K. The heat of decomposition ranges between 8.7 and 12.5 J g 21 . Some trends of variation of these parameters appear significant and are discussed in terms of solvent (matrix) and viscosity effects on the decomposition reactions. The shear modulus at 1 Hz frequency was determined at the temperature of maximum rate of foaming agent decomposition, and differs significantly from a sample to another. The foam density was determined at ambient temperature and the volume fraction of bubbles was used as criterion to judge the efficiency of the foaming process. The results reveal the existence of an optimal shear modulus of the order of 2 kPa that corresponds roughly to plasticizer molar masses of the order of 450 6 50 g mol 21 . Heavier plasticizers, especially polymeric ones are too difficult to deform. Lighter plasticizers such as diethyl phthalate (DEP) deform too easily and presumably facilitate bubble collapse.

Compression behavior of soft PVC foams obtained by cardanol-derived plasticizer

“…In particular, due to the presence of two NH 2 groups in AZDC, hydrogen bonds can be established between foaming agent and the polar groups of the plasticizer, and can influence the decomposition kinetics. 28 In DEHP, the presence of the carbonyl ester groups, characterized by a high polarity, can therefore lower the activation energy and the temperature of onset of foaming, compared to ECA. As clearly observed, the thickness of ECA plasticized PVC grows faster than that of DEHP plasticized PVC, which indicates a higher efficiency of the foaming process.…”

Development of Eco-Friendly Polymer Foam Using Overcoat Technology of Deodorant

“…Then the PVC mixture was bar-coated on the release paper (the wet thickness ≈ 1 mm). The bar-coated PVC mixture was foamed in a convection oven at 230 °C for 2 min 10 s [ 4 ]. After foaming, the PVC foam was cooled at room temperature for 1 h. A deodorant and UV-curing agent were mixed at a solid ratio 1:1 and dispersed by sonication for 3 min.…”

“…Polymer foams have many useful attributes such as flexibility, low density, impact resistance, and heat transfer capacity compared with conventional rigid polymers [ 1 ]. These features make them useful in everyday life for artificial leather, shoes, foam wallpaper, floor coverings, automobile interior trim, mats, and toys and so on as illustrated in Figure 1 [ 2 , 3 , 4 , 5 ]. Among the foaming agents that are needed to foam the polymer [ 6 , 7 , 8 ], azodicarbonamide (ADCA) is the most widely used chemical foaming agent since it has the only self-extinguishing property and excellent storage stability [ 9 , 10 , 11 ].…”

A study on fabrication of nanocomposite polyethylene foam through extrusion foaming procedure

“…10 Nanomaterials not only improve the morphology and properties of solid polymers but also act as a nucleating agent in the foaming process of these polymers which leads to the decrease of cell size and increase of cell density. [11][12][13][14][15] The first development of microcellular foams was carried out in the early 1980s using the solid-state foam method. 16 After the introduction of microcellular foams by Martini et al 17 in 1981, in 1993, Park 18 researched microcellular foam production systems.…”