The table below shows dosage in ppm of the actives in both DNOC and PNP versus resulting polymer levels in ppm. Too much polystyrene will cause fouling of the equipment and result in an inefficient process. Divinylbenzene                1500—2000 Additive TBC 85% Methanol UN 2920 CL 8-3 PG II Cas nr. AT DE FR GB IT. The above data shows that PNP is far more effective at equal dosage and almost as effective at one-fourth the dosage of DNOC and field testing has shown even greater effectiveness. Styrene production and chemistry are treated in the Kirk-Othmer Encyclopedia of Chemical Technology, John Wiley and Sons, New York 1982 (Vol. All data are not yet available, however, preliminary studies indicate that PNP is some 20 times less toxic. ��^��Ȳ��`=��x��u6Lq��` �Kma,������ٳ9���/>�S����I�>�����AK>{��;@0�y�h��B���-t~�]>��m�գ&��G4%}4�I)�و����k�̭���90�+�6�˟8�������) �j� x��=k�7��]�����LO���f.�U����}����^�43Ҍ*�4��8���G��n�j)W��5j� A @}�l�_�����Ο�����M��������?~�_��_ܮ7��z���߲�_d�~���9�$��k����K��"�,�-�>��/����N7�a3��o��ǧO�_����}\=}B�B�S�2��*��k����'Ev��>�u����}���'/T��N ���2��d��Gϩ�T`�wP!lG�v �h&XqY�V4y]Gh�_����v9?+�8nI��u�%'U�w�:��D. SUMMARY OF THE INVENTION A solution of PNP in the solvent n-methylpyrollidone (NMP) is a highly effective system for inhibiting the polymerization of styrene and its analogs and for general use in inhibiting polymerization of vinyl and other addition polymerizable monomers during their production from the various feedstocks. We the professional manufacturer of TBC. Some results from reflux tests are as follows: A sample of the monomer is washed with NaOH and water to remove any phenolic inhibitors, such as tert-butylcatechol, placed in distillation flask under nitrogen and distilled until polymer starts to form. 0000182159 00000 n The study was done on two different stops in the styrene process (the Recycle Column and the Continuous Column). 1. Add:234-5#, Zhonghua Street, Liaoyang, Liaoning Province, China   Tel:+86-419-3710666 3711016   E_mail: sales@liaodongchem.com. 1 illustrates polymer levels in the Recycle Column during the course of the trial. Pay attention to fire-proof, explosive-proof, water-proof and pollution-proof. The process of producing styrene comprising the use of a solution of paranitrosophenol in n-methyl pyrollidone as a polymerization inhibitor during said process. Slightly dissolving hot water, and it is easy to be moisture absorption and oxidation. Polymerisation inhibitors (US: polymerization inhibitors) are chemical compounds added to monomers to prevent their auto-polymerisation. 0000001471 00000 n 162 0 obj << /Linearized 1 /O 165 /H [ 1740 677 ] /L 488307 /E 184714 /N 10 /T 484948 >> endobj xref 162 56 0000000016 00000 n 0000037130 00000 n 3. H���MO�0���s�Jd���9. Square of rate of polymerization of styrene at 70.0° as a function of dimethyl-N-(2-cyano-2-propyl)-ketenimine concentra­ tion 91 Figure 3• Inhibition of azo-bis-isobutyronitrile initiated polymerization of styrene at 70.0° by diphenylpicrylhydrazyl 101 Figure 4. Purified monomers stored at ambient temperatures are of less risk of polymerising and as such the most highly reactive inhibitors are rarely used at this stage. Mean polymer levels in the Recycle Column are 455 ppm with only 125 ppm of PNP actives, hence, 10 times more effectiveness with one-fifth the dosage. 8. The styrene conversion rate is about 60% and the yield is about 90%. 0000007476 00000 n 500 ppm 4, ,000 ppm 3,500-5000 ppm, DNOC 465 ml/min 46,000 ppm 39,000-55,OOOppm, Kind code of ref document: 0000003610 00000 n Make the 85% methanol solution TBC into 2%wt solution by partial styrene.Packing,transportation,storage and notice 3 0 obj 0000183410 00000 n A recent trial at the sytrene unit in a commerical plant showed the PNP/NMP solution to be about 10 times more effective than DNOC in polymer reduction at one-fifth the dosage. Use:It is the high efficiency polymerization inhibitor during monomer distillation or storage or transportation of olefin. 0000182410 00000 n :amW'���\t.^uZX����""�"iJ�TArVE�.�_�l�[ngR����n������}szd9(�,Vo6w��(���.�k5��~ys$\R�j��〣�p��,I�+� ǁ��UVH�"�� p��?F%n%�h@uP��gm��Y7Z�\�)!B���&z*���$ m��&E�c���^R )Z8�X?�L�zyHH����'j_��ڼ(�� z(i����_]��A[�[�1WTԶ �?Ut�*S�B�J�S���hv�@��]�2{��~ !-p)���*��$��߯�~��%B$�Q��}�O(���/���\ٶݛ����ڎ���wdy�@�e ��,����F���V��Xh� S2�$�5Y�/�7��VN�p�Ԑ��;��`�*����Gj���jߍ�o�?Cx"/y��E <> 0000006158 00000 n 0000183159 00000 n Properties:Appearance: white or canary crystal; molecular weight: 166.21; Density d25601.049;Dissolving in methanol, alcohol, benzene, toluol, acetone, etc. 0000010272 00000 n 0000099289 00000 n The problem with the use of DNOC and its analogs is extreme toxicity. Retarders display no induction period but provide a permanent decrease in the rate of polymerisation, while themselves being degraded only slowly. 0000011475 00000 n Quality standard:Executive Q/LYJH05—2005. 6. The liquid TBC the derivative of Solid TBC with the same physical properties as solid TBC. ��!�e�|M���~��t�{��J���h�Ml�(�(�.�-�#½k�֦)A�Q� Styrene for example is distilled at temperatures above 100 °C whereupon it undergoes thermal polymerisation at a r… It is standard practice throughout the styrene industry to add a chemical inhibitor of some kind to help control polymerization. The polymerization inhibitor system of claim 1 wherein the monomers are selected from the group consisting of styrene, divinyl benzene, chlorostyrene, butadiene, isoprene, vinyl chloride, acrylic acid, and methacrylic acid.