Knowledge base

Many survey indicate that the majority of people perceive the chemical industry as athreat to the environment. Despite the efforts made to improve our environmentalperformance, many people continue to distrust the industry. Although one can find anumber of reasons for less-than-spectacular results, the lack of information has beenrecognized as a ma

UV curable systems continue to penetrate new markets and succeed in an increasingnumber and variety of applications. These applications pose challenges for the enduser, the formulator and the UV equipment supplier, to meet ever higher standards forcure performance and efficiency. Over the past years much effort has been centred onimprovements in ne

The productivity and efficacy of an UV curing unit is very often judged only bystating the specific power of the installed UV lamps. But the quality of an UVcured product is determined by the spectral UV irradiance ) and the spectralUV dose to which the product has been exposed. So there is some need toevaluate the relationship of the specific powe

Shrinkage is due to double bond polymerization and maximum shrinkage can be readilycalculated from the densities of monomers and polymers (based on chemical composition).Maximum shrinkage can be also estimated from functionality and molecular weight ofmonomers. Differences observed between experimental shrinkage and calculated maximumshrinkage for

The adverse effect of oxygen on the curing of acrylic systems is well known and referredto as oxygen inhibition. Molecular oxygen has, due to its ground state "biradical" nature, ahigh reactivity towards radical species which yields peroxy radicals of rather low reactivityin respect of initiating capacity. An effectively propagating radical, e.g. a

High molecular weight anlonlc block copolymerwere brought to the market place some 30 yearsago. Based on feedstocks which can bepolymerised through anionic polymerisation (e.g.lsoprene, butadiene or styrene), such styrenic blockcopolymers (SBC's) are nowadays available in anon-hydrogenated (SIS, SBS) and in ahydrogenated form (SEBS, SEPS). At roomt