Polyamide - semi-aromatic

Semi-aromatic polyamides, polyphthalamide (PPA), polyarylamide (PAA), transparent amorphous polyamide (PA-T)... 

The continuous use temperatures in an unstressed state are generally estimated at 80°C to 180°C according to the subfamily, the grade and the service conditions. For given grades, which are not representative of all semi-aromatic polyamides, maximum temperatures are ... 

Creep is rather low or very low, the more so as semi-aromatic polyamides are very often reinforced with high glass fibre contents. It changes moderately when the temperature rises. 

Semi-aromatic polyamides absorb less water than PA 6 and 66 and are less sensitive to it. Special grades are marketed for their hydrolysis resistance. 

Table 4.50 Neat and reinforced semi-aromatic polyamides examples of properties...

ANALYSIS OF THE FRACTURE BEHAVIOR OF AMORPHOUS SEMI-AROMATIC POLYAMIDES... 

Fracture, semi-aromatic polyamides, plastic zone, entanglements, molecular mobility, relaxations. 

In recent years, the relaxation and yield behavior of amorphous semi-aromatic polyamides has been the subject of a detailed analysis at the molecular level [1-6], Two series of materials were investigated, so-called SAPA-R and SAPA-A (Table 1). In the SAPA-R series, the chemical structure is based on isophthalic or terephthalic acid and 2-methyl 1,5-pentanediamine. In the SAPA-A series, the chemical formulae include isophthalic or terephthalic acid residues, diamino dimethylcyclohexylmethane residues, and lactam-12 sequences. 

Analysis of the Fracture Behavior of Amorphous Semi-Aromatic Polyamides... 

There is a great diversity of amorphous aromatic or semi-aromatic polyamides (PARA). The commercial resins include Trogamid , Quiana , Amodel , etc. They have been blended to improve the mechanical properties and impact strength, as well as to enhance the barrier properties of the matrix resin to permeation by gases or liquids. Examples of blends with PARA are listed in Table 1.75. Blends of PARA were also discussed along other blends of polyamides. 

MXD6 and PA-61, respectively, show different miscibility, e.g., with aliphatic PA s. Clearly, blind application of the segmental interaction strategy to aromatic or semi-aromatic polyamides could lead to conflicts. However, the problem can be resolved considering p and m substituted phenyl as two different statistical segments [Ellis, 1995]. This idea is indeed evident in the segmental contributions listed in Table 2.11. 

Cao M, Xia S, Huang X, Cai T, Zeng X. Semi-aromatic polyamide and a method for preparation with low wastewater discharge. 

Anada A, Tamura K, Munesawa Y. Semi-aromatic polyamide film, and process for production thereof. US Patent Application 20130231424, assigned to Kuraray Co., Ltd., Okayama, JP, and Unitika Ltd., Hyogo, JP 2013. 

Rulkens R. Semi-aromatic polyamide. US Patent Application 20130150525 2013. 

Gu H, He JM, Hu J, Huang YD. Thermal degradation kinetics of semi-aromatic polyamide containing benzoxazole unit. J Therm Anal Calorim 2012 107(3) 1251-7. 

Orihashi Y. Semi aromatic polyamide resin compositions, processes for their manufacture, and articles thereof. US Patent Application 20110015328, assigned to E.I. Du Pont de Nemours and Company, Wilmington, DE 2011. 

Polyamides are abbreviated as PA, followed by the number of carbons in a diamine and dicarboxylic acid, viz., PA-66 has six carbons in each component, etc. Poly-E-caprolactam or polyamide-6 (PA-6) was first studied by Von Brown in 1905-1910, and 30 years later commercialized as PerloriP. In the year 1936, PA-66 and several other aliphatic and semi-aromatic polyamides were disclosed (Carothers 1937). Two years later, du Pont introduced Nylon . PA-11 was commercialized in 1955, PA-12 in 1966, PA-612 in 1970, and PA-46 in 1987. In 1976 du Pont started production of the super tough PA blends (Damm and Matthies 1990). In 1991 consumption of the thermoplastic PAs was estimated at 1.2 Mt. Comparative properties of the better-known PAs are listed in Table 1.54. 

Ixef Semi-aromatic polyamide, PA, polyarylamides, with GF or mineral Solvay Cie SA... 

Ultramid T Semi-aromatic polyamide-6/66, PA-66 T, or PARA with elastomer 30 wt% glass fiber or mineral filled BASF Plastics... 

S. Zulfiqar, A. Kausar, M. Rizwan, and M. I. Sarwar, Probing the role of surface treated montmorillonite on the properties of semi-aromatic polyamide/clay nanocomposites. Applied Surface Science, 255 (2008), 2080-86. 

Polyphthalamides were originally developed for use as fibers and later found apphcation in other areas. They are semi-aromatic polyamides based on the polymerization of tereph-... 

The temperature indices according to UL 746 as a function of minimum thickness for differently modified semi-aromatic polyamides are ... 

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