Ethylene Propylene Terpolymers

1967 ◽  
Vol 40 (2) ◽  
pp. 569-589 ◽  
Author(s):  
R. German ◽  
G. Vaughan ◽  
R. Hank
Keyword(s):  
Molecular Weight ◽  
Raw Materials ◽  
General Purpose ◽  
Random Copolymers ◽  
Technological Properties ◽  
Ethylene Propylene ◽  
The Third ◽  
Low Degrees ◽  
Accelerator System ◽  
Controlled Structures

Abstract The general technological properties of a polymer are closely related to its molecular structure. It is, therefore, important to know polymerization methods by which to produce reproducible polymers with controlled structures. Use of several monomers in copolymerization significantly increases the difficulty of this problem, but in the end it leads to a much wider spectrum of raw materials. In addition to variations caused by changes in molecular weight and in molecular weight distribution the nature of copolymers may be altered by changing the composition of the monomer mixture and the way monomers are distributed in the polymer chain. Use of Ziegler-Natta catalysts has already given a multiplicity of materials composed of ethylene and propylene: random copolymers are particularly interesting as rubbers. Introduction of a third component to give unsaturation in the terpolymer, so that this may be vulcanized with sulfur and accelerators, has greatly increased the possible areas of application for these polymers. Utility of a diene as the third component to give EPT's which can be used as general purpose rubbers depends on its price, the ease with which it copolymerizes through one double bond, its influence on the velocity or steric course of the ethylene-propylene copolymerization, vulcanization characteristics of the resulting terpolymers, and finally on the technological properties of the vulcanizates. The amount of copolymerized termonomer should be limited to retain the advantageous chemical and physical properties of the original ethylene-propylene copolymers. However very low degrees of unsaturation limit the sulfur and accelerator system, the characteristics of which depend strongly on the structure of the terpolymer as well as on the nature and form of the vulcanization agent. It is therefore essential to have a thorough understanding of this multiple interdependency for optimal application of the materials. We describe here reproducible procedures for production of terpolymers with controlled structures, and the course of vulcanization of the products in relation to terpolymer structure. We shall describe methods, based on these investigations, which may be applied for control of the vulcanization characteristics of the polymers.

Synthesis and Elastomeric Properties of Copolymers of Butadiene and 1,3-Pentadiene

1973 ◽  
Vol 46 (5) ◽  
pp. 1274-1284 ◽  
Author(s):  
A. Carbonaro ◽  
V. Zamboni ◽  
G. Novajra ◽  
G. Dall'Asta
Keyword(s):  
Abrasion Resistance ◽  
Room Temperature ◽  
Composition Range ◽  
General Purpose ◽  
Random Copolymers ◽  
Technological Properties ◽  
Vanadium Compounds ◽  
Catalyst Systems ◽  
Trans Structure ◽  
Aluminum Halides

Abstract Random copolymers of all trans structure have been prepared from butadiene and 1,3-pentadiene, in the presence of vanadium compounds and alkyl aluminum halides composed catalyst systems. Copolymers of butadiene and pentadiene, in the composition range of 30-45 weight per cent of pentadiene, are amorphous at room temperature at rest but crystallize upon stretching. Cured tread stocks show improved technological properties with respect to other synthetic diene-based elastomers. Very good processing and extrusion behavior, high tack, tear strength, and abrasion resistance are outstanding properties of the BP copolymers in the field of general purpose rubbers.

scholarly journals Absorption of sugars by the piglet

1968 ◽  
Vol 22 (3) ◽  
pp. 501-514 ◽  
Author(s):  
D. E. Kidder ◽  
M. J. Manners ◽  
M. R. McCrea ◽  
A. D. Osborne
Keyword(s):  
Molecular Weight ◽  
Small Intestine ◽  
Polyethylene Glycol ◽  
High Molecular Weight ◽  
Alimentary Tract ◽  
The Third ◽  
Sugar Mixtures

1. Diets containing various sugar mixtures together with polyethylene glycol of high molecular weight as a marker were fed to pigs 1, 2 and 3 weeks old. The piglets were slaughtered 2.5 h later, and the ratio of sugar to marker was determined in the contents of the alimentary tract as far as the caecum.2. The greatest fall was found in the first part of the small intestine.3. Glucose had always disappeared by the third quarter of the small intestine.4. Xylose and fructose disappeared more slowly, especially in the younger pigs, but were usually absent from the contents of the last quarter of the small intestine.5. Sucrose was removed far less completely, and the ratio of sucrose to marker frequently did not decrease along the second half of the small intestine. Sucrose was removed much less efficiently when it formed 15% of the diet than when it formed only 5%, and much less efficiently by the younger than by the older pigs.

The Roman Ceramics of Salobrena (Granada-Spain) and their Raw Materials

1992 ◽  
Vol 267 ◽  
Author(s):  
Ana M De Andres ◽  
Isabel MuÑOZ
Keyword(s):  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Raw Materials ◽  
Third Century ◽  
Western Coast ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Third ◽  
Good Number ◽  
Scanning Electron

ABSTRACTNineteen roman ceramic sherds found near Salobreña (Granada, Spain), in the western coast of the Mediterranean Sea, as well as different ceramic clays from the surroundingsare studied. Both clays and ceramic sherds are characterizad by X-ray diffraction and spectrometry, differential thermal analysis, and scanning electron and optical microscopies. A good number of the ceramic pieces, among which some “Terrae Sigillatae”, have a composition similar to that of the local clays and, thus, have been probably manufactured at Salobreña. Only a few of them have a foreign origin. For most of them, the firing temperature was about 800-850 °C, although some have been produced at 900-1000 °C, and some others at 1000-1100 °C. It is concluded that Salobreña appearsto have been an important settlement just in the third century of the Christian era.

Preparation of n-Alkylacrylate and Vinyl Acetate Copolymer and Its Influence on Low-Temperature Fluidity of Diesel Fuel

2011 ◽  
Vol 236-238 ◽  
pp. 708-714 ◽  
Author(s):  
Hong An ◽  
Shu Gang Gao ◽  
Shuang Li ◽  
Yan Xin Xie
Keyword(s):  
Molecular Weight ◽  
Low Temperature ◽  
Vinyl Acetate ◽  
Diesel Fuel ◽  
Mass Fraction ◽  
Raw Materials ◽  
Cold Filter Plugging Point ◽  
Point Depressant ◽  
Petrochemical Company ◽  
Acetate Copolymer

The n-tetradecylacrylate-vinyl acetate copolymer (PPV) was prepared from n-tetradecylacrylate and vinyl acetate. The PPV was employed as pour point depressant to improve the low-temperature fluidity of the -20# diesel from Daqing Petrochemical Company. The result indicated that the solidification (SP) and the cold filter plugging point (CFPP) were affected largely by PPV. And when mass fraction of PPV -14(copolymerization conditions: 80 °C,w（benzoyl peroxide）1％（total weight of raw materials）, n（vinyl acetate）∶n（n- tetradecanolacrylate） = 4∶1 ) in diesel fuel was 0.1%wt, the SP reduced by 15.0 °C, the CFPP reduced by 6.0 °C simultaneously; We analysise the different molecular weight of PPV-14, and discover that the molecular weight of PPV-14 is ralated to the the low-temperature fluidity of the -20# diesel from Daqing Petrochemical Company. When mass fraction of PPV -14(molecular weight is 15000, distribution coefficient is 3.11) in diesel fuel was 0.1% wt, the SP reduced by 18.0 °C, the CFPP reduced by 7.0 °C, simultaneously.

COMPARATIVE ASSESSMENT OF MILK PROTEIN COAGULANTS OF DIFFERENT ORIGIN

2021 ◽  
Author(s):  
А.Г. КРУЧИНИН ◽  
С.Н. ТУРОВСКАЯ ◽  
Е.Е. ИЛЛАРИОНОВА ◽  
А.В. БИГАЕВА
Keyword(s):  
Dairy Products ◽  
Milk Protein ◽  
Proteolytic Enzymes ◽  
Raw Materials ◽  
Technical Information ◽  
Animal Origin ◽  
Technological Properties ◽  
Recombinant Enzymes ◽  
Rennet Coagulation ◽  
Milk Coagulation

Потребность в увеличении количества и качества производимой молочной продукции стимулирует исследования, направленные на повышение эффективности переработки молочного сырья, что, в свою очередь, невозможно без изучения технологических свойств молока и функционально необходимых ингредиентов, применяемых в производстве различной молочной продукции. На основе научно-технической информации международных и российских баз данных, систематизированной в рамках изучаемой тематики, представлен обзор научных работ о коагулянтах белков молока различного происхождения, применяемых при кислотной, кислотно-сычужной и сычужной коагуляции. Установлено, что в российской и международной производственной практике востребованы коагулянты животного, микробного и рекомбинантного происхождения. Наибольшим спросом среди коагулянтов животного происхождения пользуется химозин, получаемый из желудков телят. Ферменты микробного и рекомбинантного происхождения отличаются более стабильным качеством и низкой стоимостью, но их производство, основанное на методах генной инженерии, вызывающих предубеждение у большинства потребителей, практически полностью сосредоточено за рубежом. При условии повышения лояльности потребителей ферменты рекомбинантного происхождения могут стать наиболее перспективными функциональными ингредиентами. Исследования потенциала различных протеолитических ферментов растительного происхождения выявили невысокий технологический эффект их применения. Рассмотренный материал позволяет прогнозировать перспективность научных исследований по выявлению механизмов коагуляции молока и новых эффективных и универсальных коагулянтов совокупно с селекционной практикой отбора животных, направленной на улучшение технологических свойств молочного сырья. The need to increase the quantity and quality of dairy products encourages research aimed at improving the efficiency of processing dairy raw materials, which, in turn, is impossible without studying the technological properties of milk and functionally necessary ingredients used in the production of various dairy products. On the basis of scientific and technical information from international and Russian data bases, systematized within the framework of the subject under study, a review of scientific works on milk protein coagulants of various origins used in acid, acid-rennet and rennet coagulation is presented. It is established that coagulants of animal, microbial and recombinant origin are in demand in the Russian and international production practice. The greatest demand among coagulants of animal origin is chymosin, obtained from the stomachs of calves. Microbial and recombinant enzymes are characterized by more stable quality and lower cost, but their production, based on genetic engineering methods that cause prejudice among most consumers, is almost entirely concentrated abroad. If consumer loyalty is increased, recombinant enzymes may become the most promising functional ingredients. Studies of the potential of various proteolytic enzymes of plant origin revealed a low technological effect of their use. The considered material allows us to predict the prospects of scientific research to identify the mechanisms of milk coagulation and new effective and universal coagulants together with the breeding practice of animal selection, aimed at improving the technological properties of dairy raw materials.

Technological aspects of alcohol distillates production from non-traditional sugar-raw materials

2021 ◽  
Vol 9 (16) ◽  
pp. 90-97
Author(s):  
Kateryna Danilova ◽  
◽  
Oksana Zavarzina ◽  
Keyword(s):  
Raw Materials ◽  
Biologically Active ◽  
Raw Material ◽  
Material Base ◽  
Growth Substances ◽  
Technological Properties ◽  
Actual Problem ◽  
Cane Molasses ◽  
Yeast Biomass ◽  
Nitrogen Phosphorus

An actual problem of the alcohol industry development is the expansion of the raw material base through the use of new, cheaper types of carbohydrate sources. Recently, glucose-fructose syrup has been of increasing interest to producers of ethanol. Among the producers of craft drinks, in particular rum-based drinks, cane molasses is in increasing demand. The article presents the technological aspects of the fermentation process of nonconventional sugar-containing raw materials on the example of glucose-fructose syrup and cane molasses in ethanol by different yeast strains. It is determined that glucose-fructose syrup and cane molasses are raw materials depleted of nitrogen, phosphorus and growth substances necessary for the yeast activity. To improve the technological properties of raw materials in the molasses, nitrogen, phosphorus nutrition and corn extract as a growth substance shall be added to a mash. Glucose-fructose syrup is of pH 3.68 and of acidity 0.12, which negatively affects the fermentation. It is established that in order to create optimal living conditions for yeast, it is necessary to add substances to the glucose-fructose syrup that will contribute to the safety of development and prevent the pH 3.5. It was determined that the alcohol yield from 1 ton of glucose-fructose syrup is 31.0 dal, from 1 ton of cane molasses is 24.0 dal on the yeast 46ED and 22 dal on the TegaYeast without the use of growth substances and vitamins necessary for the reproduction of yeast biomass. Under conditions of improving the technological properties of the mash from the glucose-fructose syrup and cane molasses by adding biologically active substances promoting the synthesis of yeast biomass, the ethanol content in the fermented mashes increases up to 11.9 12% vol.

Microstructure of Ethylene/Propylene Random Copolymers Prepared by a Fluorinated Bis(phenoxy-imine)Ti Catalyst

2006 ◽  
Vol 58 (5-6) ◽  
pp. 903-911 ◽  
Author(s):  
Zixiu Du ◽  
Junting Xu ◽  
Xin Wang ◽  
Zhiqiang Fan
Keyword(s):  
Random Copolymers ◽  
Ethylene Propylene

scholarly journals THE STUDY OF LOW-LACTOSE MILK WHEY STRUCTURE AND MODEL SYSTEMS ON ITS BASIS

2020 ◽  
Vol 3 ◽  
pp. 38-48
Author(s):  
Victoriya Gnitsevych ◽  
Tatiana Yudina ◽  
Yuliia Honchar ◽  
Olena Vasylieva ◽  
Liudmyla Diachuk
Keyword(s):  
Particle Size ◽  
Fractional Composition ◽  
Raw Materials ◽  
Model System ◽  
Model Systems ◽  
Equivalent Diameter ◽  
Contact Method ◽  
Technological Properties ◽  
Milk Whey ◽  
Crystal Diameter

This study developed a technology of low-lactose semi-finished products, based on fermented whey and pumpkin pulp puree, and offered a possibility of its use in the technology of structured culinary products. This research carried out the required substantiation of the methods of preliminary processing of raw materials, and studied the technological properties and structure of model compositions with their use. During the experiment, a number of studies were carried out, which substantiated the method and modes of condensation of whey, and provided a comparative analysis of the homogeneity of lactose-free and lactose-containing samples of whey under various modes of condensation. The study obtained the results of calculations of the equivalent diameter of the studied samples of lactose-containing and low-lactose whey, condensed by the contact method and in vacuum. It was found, that the structure is homogeneous at a number average crystal diameter of up to 5 μm. The restriction is valid for CLLWV with a calculated diameter of about 3.84 μm with a coefficient of variation of 1.35 % with an increase of 10,000 times. The study revealed the alternation of smooth and granular sections of the micron level (0.1 ... 5 μm) in the structure of the studied low-lactose semi-finished product with an increase of 300 times. It was determined, that the extremum of the differential curve of the particle size distribution of CLLWV corresponds to the number average crystal diameter of 3.84 μm. It was established, that the most homogeneous fractional composition is inherent in the studied sample of CLLWV, for which the values of fraction diameters are in the range from 1.46 μm to 4.96 μm. The optimal ratio of the components of the model CLLWV: FPPP system was determined as 70 % to 30 % respectively. With this composition, the model system is characterized by the formation of protein-pectin complexes, which is confirmed by microscopy with a magnification of 90 times

scholarly journals Extraction and Characterization of Gelatin from Skin By-Products of Seabream, Seabass and Rainbow Trout Reared in Aquaculture

2021 ◽  
Vol 22 (22) ◽  
pp. 12104
Author(s):  
Jesus Valcarcel ◽  
Carolina Hermida-Merino ◽  
Manuel M. Piñeiro ◽  
Daniel Hermida-Merino ◽  
José Antonio Vázquez
Keyword(s):  
Molecular Weight ◽  
Rainbow Trout ◽  
Raw Materials ◽  
Gel Strength ◽  
Current Trends ◽  
First Case ◽  
Imino Acids ◽  
Increasing Demand ◽  
A Minor ◽  
By Products

The expansion of fish filleting, driven by the increasing demand for convenience food, concomitantly generates a rising amount of skinning by-products. Current trends point to a growing share of aquaculture in fish production, so we have chosen three established aquaculture species to study the properties of gelatin extracted from their skin: rainbow trout, commonly filleted; and seabass and seabream, marketed whole until very recently. In the first case, trout skin yields only 1.6% gelatin accompanied by the lowest gel strength (96 g bloom), while yield for the other two species exceeds 6%, and gel strength reaches 181 and 229 g bloom for seabass and seabream, respectively. These results are in line with the proportion of total imino acids analyzed in the gelatin samples. Molecular weight profiling shows similarities among gelatins, but seabass and seabream gelatins appear more structured, with higher proportion of β-chains and high molecular weight aggregates, which may influence the rheological properties observed. These results present skin by-products of seabream, and to a minor extent seabass, as suitable raw materials to produce gelatin through valorization processes.

scholarly journals Indene dimerization products

2002 ◽  
Vol 67 (6) ◽  
pp. 393-406 ◽  
Author(s):  
Jovan Jovanovic ◽  
Michael Spiteller ◽  
Wilhelm Elling
Keyword(s):  
Molecular Weight ◽  
X Ray ◽  
Alkylation Product ◽  
The Third ◽  
Product Mixture ◽  
Acid Catalyzed ◽  
Model Substances ◽  
Pyrolysis Oils

The reaction of 1H-indene (indene) in the presence of Friedel-Crafts acids was studied. As expected [M. Spiteller, J. Jovanovic, Fuel 78(1999)1263] there were dimers and trimers in the product mixture together with higher oligomers. Among products with double molecular weight relative to the molecular weight of indene, the structure of four compounds was determined: 6-(2?,3?-dihydro-1?H-inden-1?-yl)-1H-indene 2-(2?,3?-dihydro-1?H-inden-1?-yl)-1H-indene 1-(2?,3?-dihydro-1?H-inden-2?-yl)-1H-indene and 2,3,1?,3?-tetrahydro-[1,2?]biindenylidene. It was shown that the first one represents an indene alkylation product and that the others were obtained by bonding of the indan-1-ylium ion and indene at the position 2, followed by acid catalyzed 1,2-hydride rearrangement in the case of the third and fourth one. Considering the indene dimerization products as components of pyrolysis oils and as interesting compounds to be used as model substances for NMR, MS and X-ray analysis, the reaction, separation and isolation parameters were optimized in this study.

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