Polyester resins laminates

Phosphate esters (alkyl or aryl, or mixed) of phosphoric acid constitute an important family of organophosphorus flame retardants.25 Triethylphosphate, a colorless liquid boiling between 209°C and 218°C, and containing 17 wt % phosphorus, has been used commercially as an additive for polyester resins/laminates and in cellulosics. In polyester resins, it functions as a viscosity depressant as well as a flame retardant. Trioctylphosphate is employed as a speciality flame-retardant plasticizer for vinyl composites where low temperature flexibility is critical. It can be also included in blends, along with general purpose plasticizers, such as phthalate esters, to improve low temperature flexibility. 

As the submarine was too fragile to move, the only practical conservation method was to wash the vessel in situ. A tank was constructed from glass fibre - reinforced polyester resin laminate. The structure was prefabricated in sections away from the museum and assembled on site with no disturbance to... 

Howe, R.J. and Owen, M.J., Cumulative damage in CSM/polyester resin laminates, BPF 8th International Reinforced Plastics Conference, Brighton, 1972. 

Figure 5.277 shows an example of acceptable tensile strength as a function of outer fiber strain for a mat and a non-woven laminate with UP and EP matrix. Laminates with a polyester resin matrix and an epoxy resin matrix are also provided for comparison. The acceptable residual strength continuously decreases with increasing outer fiber strain. This is more pronounced in epoxy resin laminates than in polyester resin laminates. Sulfuric acid penetrates relatively easily into epoxy resins. The activation energy of penetration depends on the acid concentration and is higher for weakly concentrated acids than for highly concentrated acids. It is over-... 

Owen, M.J. Static and Fatigue Strength of Glass Chopped Strand Ma Polyester Resin Laminates, ASTM STP 772, p. 64 - 84, 1982... 

L-P-383 Glass Fiber Base, Low Pressure Polyester Resin Laminated... 

TrialkylPhosphates. Triethyl phosphate [78-40-0] C H O P, is a colorless Hquid boiling at 209—218°C containing 17 wt % phosphoms. It may be manufactured from diethyl ether and phosphoms pentoxide via a metaphosphate intermediate (63,64). Triethyl phosphate has been used commercially as an additive for polyester laminates and in ceHulosics. In polyester resins, it functions as a viscosity depressant as weH as a flame retardant. The viscosity depressant effect of triethyl phosphate in polyester resins permits high loadings of alumina trihydrate, a fire-retardant smoke-suppressant filler (65,66). 

Mechanical Properties. The performance of various polyester resin compositions can be distinguished by comparing the mechanical properties of thin castings (3 mm) of the neat resin defined in ASTM testing procedures (15). This technique is used widely to characterize subtle changes in flexural, tensile, and compressive properties that are generally overshadowed in highly filled or reinforced laminates. 

Polyesters are eneountered in many forms. They are important as laminating resins, moulding compositions, fibres, films, surface coating resins, rubbers and plasticisers. The common factor in these widely different materials is that they all contain a number of ester linkages in the main chain. (There are also a number of polymers such as poly(vinyl acetate) which contain a number of ester groups in side chains but these are not generally considered within the term polyester resins.)... 

Stmctures present in polyester resin ready for laminating ... 

This monomer is prepared by reacting cyanuric chloride with excess allyl alcohol in the presence of sodium hydroxide at 15-20°C. Laminates based on polyester resins containing triallyl cyanurate are claimed to be able to withstand a temperaure of 250°C for short periods. 

Glass fibres are the preferred form of reinforcement for polyester resins since they provide the strongest laminates. Fabrics from other fibres may, however, be used and can in some instances provide adequate reinforcement at lower cost. Glass fibres are available in a number of forms, of which the following are the most important ... 

As mentioned in the introduction, epoxide resin laminates are much less important in tonnage terms than those for polyesters. However, in terms of value the epoxide laminates are significant. 

Not only does the material have excellent resistance to burning but smoke emission values are reported to be much less than for fire-retardant polyester resin. The laminates are being increasingly used in situations where corrosion is associated with organic media, where corrosion is encountered at temperatures above 100°C as in fume stacks and where both fire retardance and corrosion resistance are desired as in fume ducts. 

The highest mechanical strengths are usually obtained when the fibre is used in fine fabric form but for many purposes the fibres may be used in mat form, particularly glass fibre. The chemical properties of the laminates are largely determined by the nature of the polymer but capillary attraction along the fibre-resin interface can occur when some of these interfaces are exposed at a laminate surface. In such circumstances the resistance of both reinforcement and matrix must be considered when assessing the suitability of a laminate for use in chemical plant. Glass fibres are most commonly used for chemical plant, in conjunction with phenolic resins, and the latter with furane, epoxide and, sometimes, polyester resins. 

The printing ink industry uses P.Y.120 primarily for decorative printing inks on laminated melamine and polyester resin sheets. In terms of lightfastness, 8% gravure prints in 20 and 40 pm cells on such plates correspond to step 8 on the Blue Scale. Plate-out is not observed. P.Y.120 is insoluble in monostyrene and acetone (Sec. 1.8.1.2). 

The list of applications also includes decorative printing inks for laminated plastic sheets based on melamine or polyester resin. The required fastness and performance properties are very good the pigment does not, for instance, color the clear sheets. 8% gravure prints (20 pm cell depth) equal step 8 on the Blue Scale for lightfastness. 

By far the most common form of reinforcement is fiberglass. Products using unsaturated polyester resin as a matrix and fiberglass fiber reinforcements are commonly referred to as composites , laminates or FRPs (fiber-reinforced plastics). The latter reinforcements are sold as continuous roving, which is continuously chopped in place with a liquid resin stream, chopped roving mat, woven... 

Since the stiffness of a laminate varies as a cubic relationship with the thickness, there are alternate methods employed to achieve thickness - and hence stiffness - than by using multiple layers of fiberglass and resin. Lightweight core materials, such as end-grained balsa wood, high-density polyurethane foam, PVC foam, and honeycombed materials, are available. These materials are sandwiched in between layers of unsaturated polyester resin to achieve increased laminate stiffness. The common terminology used for this technique is sandwich construction . 

Jin, L. and Nava, H., High performance polyether-polyester containing laminating resin composition, World Patent Wo 0 116 207, 2001. 

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