Use of water-based carbonyl-functional polymers on a cross-linker-free highperformance leather finish
The present paper aims to study a new high-performance coating formulation while avoiding the use of cross-linkers. 
By using acrylic polymers with carbonyl functional groups, the negative environmental effects of the finishing process can be minimized. These new polymers can give very good physical properties without losing the inherent properties 
of flexibility and elasticity needed in upholstery leather
Cross-linked polymers for aqueous finishing. Binders crosslinked with polyaziridine: Part II Acrylic Binders
Due to the current stringent regulations regarding emissions into the environment, coating recipes commonly used in leather finishing comprise water-based products. However, in order to obtain the physical properties required for most leather goods, the use of reactive cross-linkers is needed. The present study aims to look into the behaviour of acrylic binders cross-linked with polyaziridine: the amount of cross-linker used, the type of polymer employed, the type of tannage and retannage and the evolution of the reaction over time. A comparison of results shows that the type of tannage and retannage, as well as the physical characteristics of the acrylic binder used are influential factors in the behaviour of acrylic binders cross-linked with polyaziridine. Different amounts of polyaziridine are needed with regard to the type of tannage and retannage and to the physical characteristics of the acrylic binder used.
The micro-mechanical behaviour of artificially cemented sand particles under compression and shear
The mechanical behaviour of cemented sands at macro-scale has been widely studied in the past, while there is still a lack of laboratory test data for the micro-mechanical response. Therefore, a series of uniaxial compression and tangential shear tests on artificially cemented sand particles have been conducted using a microscope to observe their behaviour. First, the consistency of cemented particles with different cementing agents is discussed. Three breakage modes are proposed according to the images taken using a microscope camera. A new parameter named ‘local roundness at contact’ is introduced to emphasise the effect of contact morphology on sample strength. Moreover, the effect of bond thickness on the mechanical response of cemented particles has been investigated. Finally, the shear strength parameters of artificially cemented sand samples have been determined for two different sample diameters.