Polymer additives, plasticizers

Figure 10.35. Smoke density of PVC compounds containing different plasticizers. Formulation PVC 65 wt%, plasticizer 35 wt%. Disflamoll DPO - diphenyl 2-ethylhexyl phosphate, TKP - trioresyl phosphate, DPK - diphenyl cresyl phosphate. [Data from Polymer Additives. Plasticizers, Bayer SP-PMA 8013 E,...

Figure 14.16 shows injection molding setup for production of capsules from gelatin for pharmaceutical apphcations. In this case, the main raw material is supplied in the form of a water solution or water plasticized natural polymer. Additional plasticizer is added to make the final product sufficiently flexible." ... 

At least three different uses of vegetable oils in polymer formulations can be proposed (i) as polymer additives (plasticizers, stabilizers, ete.) ... 

Selection of Polymer, Additives (Plasticizer, Flow Aid and Surfactant), and Drug Loading in HME... 

A plasticizer is a substance the addition of which to another material makes that material softer and more flexible. This broad definition encompasses the use of water to plasticize clay for the production of pottery, and oils to plasticize pitch for caulking boats. A more precise definition of plasticizers is that they are materials which, when added to a polymer, cause an increase in the flexibiUty and workabiUty, brought about by a decrease in the glass-transition temperature, T, of the polymer. The most widely plasticized polymer is poly(vinyl chloride) (PVC) due to its excellent plasticizer compatibility characteristics, and the development of plasticizers closely follows the development of this commodity polymer. However, plasticizers have also been used and remain in use with other polymer types. 

Nonionic surfactants and phenoUc resins based on alkylphenols are mature markets and only moderate growth in these derivatives is expected. Concerns over the biodegradabiUty and toxicity of these alkylphenol derivatives to aquatic species may limit their use in the future. The use of alkylphenols in the production of both polymer additives and monomers for engineering plastics is expected to show above average growth as plastics continue to replace traditional building materials. 

Ethyl Vinyl Ether. The addition of ethanol to acetylene gives ethyl vinyl ether [104-92-2] (351—355). The vapor-phase reaction is generally mn at 1.38—2.07 MPa (13.6—20.4 atm) and temperatures of 160—180°C with alkaline catalysts such as potassium hydroxide and potassium ethoxide. High molecular weight polymers of ethyl vinyl ether are used for pressure-sensitive adhesives, viscosity-index improvers, coatings and films lower molecular weight polymers are plasticizers and resin modifiers. 

There is a substantial literature on polymers and plastics and many monographs are listed at the end of individual chapters. In addition the following provide excellent comprehensive source material ... 

Poor tack. Addition of low molecular weight polymers and plasticizers, or addition of tackifiers are mandatory to obtain adequate tack. 

The words polymers and plastics are often taken as synonymous but in fact there is a distinction. The polymer is the pure material which results from the process of polymerisation and is usually taken as the family name for materials which have long chain-like molecules (and this includes rubbers). Pure polymers are seldom used on their own and it is when additives are present that the term plastic is applied. Polymers contain additives for a number of reasons. The following list outlines the purpose of the main additives used in plastics. 

Represents more than 400 manufacturers of polymers, additives, and machinery as well as all types of plastics processors and fabricators. Membership is divided into 15 Business Groups sharing four Market Sector Groups. 

A multidimensional system using capillary SEC-GC-MS was used for the rapid identification of various polymer additives, including antioxidants, plasticizers, lubricants, flame retardants, waxes and UV stabilizers (12). This technique could be used for additives having broad functionalities and wide volatility ranges. The determination of the additives in polymers was carried out without performing any extensive manual sample pretreatment. In the first step, microcolumn SEC excludes the polymer matrix from the smaller-molecular-size additives. There is a minimal introduction of the polymer into the capillary GC column. Optimization of the pore sizes of the SEC packings was used to enhance the resolution between the polymer and its additives, and smaller pore sizes could be used to exclude more of the polymer... 

Plasticizers and Other Polymer Additives (Including Phthalates)... 

Plastics additives now constitute a highly successful and essential sector of the chemical industry. Polymer additives are a growing sector of the specialty chemical industry. Some materials that have been sold for over 20 years are regarded today as commodity chemicals, particularly when patents covering their use have expired. Others, however, have a shorter life or have even disappeared almost without trace, e.g. when the production process cannot be made suitably economic, when unforeseen toxicity problems occur or when a new generation of additive renders them technically obsolete. 

For standard or proprietary polymer additive blends there is the need for analytical certification of the components. Blend technology has been developed for two- to six-component polymer additive blend systems, with certified analytical results [81]. Finally, there exist physical collections of reference additive samples, both public [82] and proprietary. The Dutch Food Inspection Service reference collection comprises 100 of the most important additives used in food contact plastics [83-85]. Reference compounds of a broad range of additives used in commercial plastics and rubber formulations are generally also available from the major additive manufacturers. These additive samples can be used as reference or calibration standards for chromatographic or spectroscopic analysis. DSM Plastics Reference Collection of Additives comprises over 1400 samples. 

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