METHOD FOR IDENTIFYING A BLEND OF NUCLEATORS USEFUL FOR PREPARING A NUCLEATED POLYOLEFIN MATERIAL

The present invention relates to a method for identifying a blend of nucleators which is advantageous for providing reduced haze in a nucleated polyolefin material compared to blends of the same nucleators having different weight ratios of components. In one aspect, the present invention provides a method for identifying a blend of at least two nucleators having a weight ratio of components that provides reduced haze in a nucleated polyolefin material compared to blends of the same nucleators having different weight ratios of components, wherein each nucleator is soluble in a molten polyolefin resin, said method comprising the steps of: i) preparing a plurality of blends of the at least two nucleators wherein each blend contains the same at least two nucleators but in a different weight ratio, wherein the plurality of blends includes one or more blends in which one of the at least two nucleators is a major weight fraction of the blend as well as one or more blends in which the same one of the at least two nucleators is a minor weight fraction of the blend; determining, for each of the blends prepared in step i), a minimum dissolution temperature at which a given concentration of each of the blends becomes completely dissolved in individual samples of the same molten polyolefin resin, wherein the concentration of each of the different blends in the individual samples is substantially the same and below the saturation point in the molten polyolefin resin and the same method for determining the minimum dissolution temperature is used for each blend; and iii) identifying a blend of the at least two nucleators which has a minimum dissolution temperature which is lower than that determined in step ii) for a majority of the plurality of blends. La présente invention décrit un procédé d'identification d'un mélange de nucléateurs qui est avantageux pour assurer un trouble réduit dans un matériau de polyoléfine nucléé comparé aux mélanges des mêmes nucléateurs présentant différents rapports en poids de constituants. Dans un aspect, la présente invention concerne un procédé d'identification d'un mélange d'au moins deux agents de nucléation ayant un rapport pondéral des constituants qui fournit un trouble réduit dans un matériau de polyoléfine nucléé par comparaison avec des mélanges des mêmes agents de nucléation ayant des rapports de poids différents de constituants, chaque agent de nucléation étant soluble dans une résine de polyoléfine fondue, ledit procédé compre