PREFACETask 1, as outlined in the original proposal, was to be a study of gas-gas mixing at the boLndary between two fast-moving gas streams. Work. on this task was postponed for the first year of the project in order to permit intensified effort -n other tasks.A review r the project as a whole, in the light of an opportunity afforded by changes in the sponsorship of related combustion oroJects, now leads us to propose replacing the task on mixing with one on polyirer decomposition rechanisms. We look upon this change as a means to strengthen the project by initiating the investigation of molecular mechaniszns of combustion, later expanding to the studty of molecular mechanisms of thermo-mechanical and chemico-mechanical behavior of propellant materials,The investigators have already reported some work on polym7%er decomposition (ArOSR Final Report 67-)901), and this work is still ir progress under other sponsorship. It has been concerned almost exclusively with measuremr!_,ts of the thermal effects attending the rapid heating of polymnes and propellant-lik. materials, very limited work having been done on the chemical aspects. The therml approach under other sponsorship should -be completed ir September 1968 anrd combined thermal and chemica-approach will be initiated as Task I under THF-MIS at that tim-e. The seve,-ai coriention.i .et --, eveloped for the study of the erma] decmposition C' polymeric and composite materials (DTA, TGA, "C) suffev from the defect that. at the sinall heating rates employed, ;e high-temperatore d.cn-.pooio: mechanisns probably active in combustion ",ocesses are not observed; thc virgin mtaterial is consumed or altered by w-.temperature mech~e 'ms before the decomicsition temperatures associated th combustion processes ;re readhe: TL: w)rk alrcady performed at this tcil.ty has employed heatii, , rates 50 to 100 times as great as those ed in conventional studies.Briefly, the studies with PBAA polymer havie revealed that, if heati;ng %es place in an inert, evircnnt, a pressure-dependent endother'm is served well before a significant amount of gaseous product is evolveJ.heating takes place in the presence of hot oxygen, or even in nitrogen en the polymer contains twenty percent or more of ammonium perchlorate, e first significant ewvnt iq an exotherm; and it is observed well before visible flame signals ignition. The dependence of the temperatures at Ich these even.s o,-rr o-heating rate, pressure, and oxygen tem-erature trits some !nfe-,rces LOcerning mechenism but serves mainly to identifyI I partial1y -to cnarac.terlze everts whse chemistry must be studitd before 3.ful result can be published, Studc2s now in progress define the problems which will be investigated Task I. The current study has yielded data concerning the polymeriger reaction which can be used to discriminate between proposed mechanisms the reaction. However, since these data were ob.tained under transient iditiris, Lneir vchanistic interpretation must account for time-dependent rder,ýture and concentration variations...

With the development of new oil formations and with the advent of new directions in the global energy sector, new requirements for materials for well construction appear. With the close attention to environmental footprint and unique properties, one of the promising materials for well cementing is geopolymers. Being a relatively new material, they are characterized by low carbon footprint, high acid resistance and attractive mechanical properties. This article is aimed at developing new geopolymer slurries for the oil industry, their characterization and field implementation analysis. With the ultimate goal of developing a methodology for the analysis of raw materials and designing the geopolymer slurries, studies were carried out on various raw materials, including different types of fly ash. Based on the data obtained and rapid screening methods, an approach was developed to formulate a geopolymer composition recipe. Since not all cement additives directly work in geopolymers, special attention was paid to control the thickening time and fluid loss. The methods of XRD, XRF, ICP-MS, density, particle size distribution measurements as well as API methods of cement testing were used to understand the composition and structure of the materials obtained, their properties and design limitations. A special approach was applied to study the acid resistance of the materials obtained and to compare with conventional cements and slags. Using one of the most common sources of aluminosilicate, fly ash, formulations with a density of 13.5 – 16.5 lbm/galUS were tested. A sensitivity analysis showed that the type of activator and its composition play a critical role both in the mechanical properties of the final product and in the solidification time and rheological properties of the product. The use of several samples of fly ash, significantly different in composition, made it possible to formulate the basic rules for the design of geopolymers for the oil industry. An analysis was also carried out on 10 different agents for filtration and 7 moderators to find a working formulation for the temperature range up to 100°C. The samples were systematically examined for changes in composition, strength, and acid resistance was previously measured. Despite the emergence of examples of the use of geopolymers in the construction industry and examples of laboratory testing of geopolymers for the oil industry, to the best of our knowledge, there has been no evidence of pumping geopolymers into a well. Our work is an attempt to develop an adaptation of the construction industry knowledge to the unique high pressure, high temperature conditions of the oil and gas industry. The ambitions of this work go far beyond the laboratory tests and involve yard test experiments.