Acrylic homopolymers table

Below T polymers are stiff, hard, britde, and glass-like above if the molecular weight is high enough, they are relatively soft, limp, stretchable, and can be somewhat elastic. At even higher temperatures they flow and are tacky. Methods used to determine glass-transition temperatures and the reported values for a large number of polymers may be found in References 7—9. Values for the T of common acrylate homopolymers are found in Table 1. 

Table 3. Solubility Parameters of Acrylic Homopolymers Calculated by Small s Method ...

As shown in Table 3, the glass transition temperature of the acrylate homopolymers is very much dependent on the nature of the alcohol that was used to make the acrylate ester. Typically, the Tg is the lowest when the number of carbons in the alkyl group (R in the formula above) is about 8-12. 

Polarity of Vinyl Acrylic Latex and Surfactant Adsorption Contact angle measurements, dispersion and polar contribution to latex film surface tension and polarity of polymer calculated according to the method of Kaelble (10) of the three latex films are whown in Table V. It is seen that the polarity of the latex film decreases with increase in butyl acrylate content of the vinyl acrylic co-polymer. The polarity of the 70/30 (VA/BA) latex is very similar to that of the polybutyl acrylate homopolymer estimated to be about 0.21 (1). ... 

The copolymer and acrylic homopolymer and copolymer latexes required for the blend systems to correspond compositionally to the two-stage latexes were prepared by a batch charged process as outlined in Table XIII. 

Table 1 Glass transition temperatures of a range of acrylic homopolymers...

Table V. General Durability Characteristics of Acrylic Homopolymers...

Table 4.8 Glass transition temperatures (Tg) of acrylic homopolymers derived from typical monomers used in medical pressure-sensitive adhesives (PSAs) ...

These empirical relationships along with the glass transition temperature data estabhshed for homopolymers (Table 9.1) allow polymer chemists to determine the optimal position of the glass transition temperature and then design adequate emulsion polymer compositions to fulfill end-users requirements. n-Butyl acrylate (T = -54°C) and 2-ethylhexyl acrylate (Tg = -85°C), for example, are widely used as the major components of water-based pressure-sensitive adhesives. Vinyl acetate and n-butyl acrylate copolymer latexes with a weight ratio of about 80 20 Tg = 8°C) are a primary choice for inte-... 

The following table lists solubility parameters for some typical acrylic homopolymers and solvents. 

The adhesion force after brief contact is called tack (Zosel, 1985,1986). Table 9.2 shows the tack of some acrylic homopolymers. The higher the amount of carbon atoms (C ) in the side chain the higher is the maximum tack, and the lower is the temperature T (max-tack) at which the maximum tack occurs. Low Tg monomers give soft and tacky polymers, in particular polyethylhexyl and polybutyl acrylate have the best tack at room temperature (Druschke, 1987). 

Table 10.3 Properties of polyurethane/acrylic IPNs compared with blends and homopolymers...

POLYCARBOXYLIC ACIDS The gamma radiolysis of the homopolymers of acrylic, methacrylic and itaconic acids have been investigated in the solid state at 303 K, and in each case the yields of carbon monoxide, carbon dioxide and of radical intermediates have been measured. These are reported in Tables VII and VIII respectively. 

The two extremes on the styrene-butadiene block copolymer composition scale are homopolymers of butadiene or styrene, respectively. To test the usefulness of homopolymers as dispersants, polybutadiene (PB) was carboxylated by adding thioglycolic acid, and polystyrene (PS) having carboxylic groups was prepared by copolymerizing small amounts of acrylic acid (AA) into the styrene chain. Adsorption experiments with these carboxylated homopolymers are listed in Table V. In the first... 

Emulsion Polymerization A typical recipe is give in Table I. Emulsion polymerization was carried out at 60°C under a nitrogen atmosphere using a batch process. Theoretical solids content in all the formulations was 25%, and generally the conversions were better than 98%. A polyvinyl acetate homopolymer and two poly (vinyl acetate-butyl acrylate) copolymers having VA/BA composition of 85/15 and 70/30 were prepared according to the above procedure. 

Spontaneous thermal copolymerizations of captodative acrylates with styrene lead to a copolymer with higher molecular weight than the homopolymer. Copolymerization parameters are summarized in Table 17 [70], Both parameters r and r2 in the spontaneous copolymerizations are in agreement with those in the AIBN-initiated copolymerizations within experimental error, supporting a radical mechanism for the spontaneous copolymerizations. 

Although no longer of significant commercial interest, the characteristics of some of the amorphous homopolymers commercially available at one time or another are illustrated in Table 4. No crystalline polymers are known to have been commercialized. This lack of commercial success results from the economically competitive situation concerning vinyl ether polymers versus other, more readily available polymers such as those based on acrylic and vinyl ester monomers. 

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