Abstract: The invention relates to the field of oligomerization of olefins to produce linear ?-olefins, in particular hexene-1, with the use of a catalyst system. The catalyst system comprises a chromium source compound, a nitrogen-containing ligand, alkylaluminum, and a zinc compound, wherein catalyst system is activated during its preparation by 1) heating some and SHF irradiation (microwave irradiation) of alkylaluminum or a mixture of the alkylaluminum and the zinc compound, or by 2) heating alkylaluminum or a mixture of the alkylaluminum and the zinc compound, followed by holding (aging) the prepared catalyst system for a certain period of time.

Abstract: Disclosed herein are modified diene-containing (co)polymers, in particular, modified styrene-butadiene copolymer, which can be used as flame retardants for expandable polystyrene polymer compositions. In particular, disclosed is a modified diene-containing (co)polymer, a method for preparing it, and use as a flame retardant for expandable polystyrene. The modified diene-containing (co)polymer claimed in the invention is characterized by high thermostability, namely, a 5% weight loss temperature of at least 180° C., a molecular weight of at least 1500 g/mol and a halogen content of at least 35 wt. %; the content of tertiary and/or allyl halogenides is in the range from 0 to less than 1.5 wt. %, and also does not affect the polymerization process and the formation of polystyrene granules either, and allows to obtain polystyrene granules with a yellowness index of 2 to 6 units, comparable to the yellowness index of polystyrene granules containing HBCD (from 0 to 3 units).

Abstract: The present invention relates to a method of preparing ?-olefins by oligomerization of C2-C4 olefins. The method is carried out by oligomerization of C2-C4 olefins in the presence of a catalyst system comprising a transition metal source, an activator, which is an alkylaluminoxane, and a compound of formula (I), Ar1Ar2P—N(R)—PAr3Ar4 [formula I], wherein Ar1-4 are the same or different and are selected from substituted or unsubstituted C6-C10 aryl, R is selected from linear or branched C1-C4 alkyl, substituted or unsubstituted C6-C10 aryl, and substituted or unsubstituted C3-C10 cycloalkyl, wherein the oligomerization is carried out in a solvent, which is a bicyclic compound or a mixture of bicyclic compounds, preferably decalin. The claimed method provides a significant increase in the activity of the catalyst during the oligomerization process and, as a consequence, a reduction in the catalyst unit consumption, as well a reduction in the formation of polymer by-product.

Abstract: Methods of preparing oligomers of an olefin are provided. The methods can include providing an alkylaluminum compound and irradiating the alkylaluminum compound with microwave radiation to provide an irradiated alkylaluminum compound. The methods can further include mixing the irradiated alkylaluminum compound with a chromium compound, a pyrrole compound, and a zinc compound to provide a catalyst composition. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

Abstract: The invention relates to the field of oligomerization of olefins to produce linear ?-olefins, in particular hexene-1, with the use of a catalyst system. The catalyst system comprises a chromium source compound, a nitrogen-containing ligand, alkylaluminum, and a zinc compound, wherein catalyst system is activated during its preparation by 1) heating some and SHF irradiation (microwave irradiation) of alkylaluminum or a mixture of the alkylaluminum and the zinc compound, or by 2) heating alkylaluminum or a mixture of the alkylaluminum and the zinc compound, followed by holding (aging) the prepared catalyst system for a certain period of time.

Abstract: The present invention relates to a method of preparing ?-olefins by oligomerization of C2-C4 olefins. The method is carried out by oligomerization of C2-C4 olefins in the presence of a catalyst system comprising a transition metal source, an activator, which is an alkylaluminoxane, and a compound of formula (I), Ar1Ar2P—N(R)—PAr3Ar4 [formula I], wherein Ar1-4 are the same or different and are selected from substituted or unsubstituted C6-C10 aryl, R is selected from linear or branched C1-C4 alkyl, substituted or unsubstituted C6-C10 aryl, and substituted or unsubstituted C3-C10 cycloalkyl, wherein the oligomerization is carried out in a solvent, which is a bicyclic compound or a mixture of bicyclic compounds, preferably decalin. The claimed method provides a significant increase in the activity of the catalyst during the oligomerization process and, as a consequence, a reduction in the catalyst unit consumption, as well a reduction in the formation of polymer by-product.

Abstract: Methods of preparing oligomers of an olefin are provided. The methods can include providing a composition that includes an alkylaluminum compound, a chromium compound, and a hydrocarbon solvent. The hydrocarbon solvent can include n-undecane, a C8-C11 alkane compound having one branch, or a mixture thereof. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

Abstract: Methods of preparing oligomers of an olefin are provided. The methods can include providing an alkylaluminum compound and irradiating the alkylaluminum compound with microwave radiation to provide an irradiated alkylaluminum compound. The methods can further include mixing the irradiated alkylaluminum compound with a chromium compound, a pyrrole compound, and a zinc compound to provide a catalyst composition. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

Abstract: Methods of preparing oligomers of an olefin are provided. The methods can include providing a composition that includes an alkylaluminum compound, a chromium compound, and a hydrocarbon solvent. The hydrocarbon solvent can include n-undecane, a C8-C11 alkane compound having one branch, or a mixture thereof. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.