DINP

The and C q iso-phthalates (DINP and DIDP) generally compete with DEHP as commodity general-purpose plasticizers. Other iso-phthalates are available at opposite ends of the carbon number range (eg, diisoheptyl phthalate (DIHP), C, and diisotridecyl phthalate (DTDP), but these serve more speciaUty markets. The Cg iso-phthalate, diisooctyl phthalate (DIOP), has also had traditional sales ia the commodity plasticizer markets where it is seen as an equivalent to DEHP. 

The Specialty Plasticizers. Eor the purpose of this article, the term specialty plasticizer refers to any plasticizer other than DEHP (DOP), DIOP, DINP, or DIDP. 

Plasticizer Efficiency. This is a measure of the concentration of plasticizer required to impart a specified softness to PVC. Such a softness of material may be measured as a British Standard Softness (BSS) or a Shore hardness (Pig. 1). Por a given acid constituent of plasticizer ester, ie, phthalate, adipate, etc, plasticizer efficiency decreases as the carbon number of the alcohol chain increases, eg, for phthalate esters efficiency decreases in the order DBP > DIHP > DOP > DINP > DIDP > DTDP. An additional six parts per hundred in PVC of DIDP rather than DOP is required to give a hardness of Shore 80 when ah. other formulation ingredients remain constant. The consequence of this depends on the overall formulation and product costs. In addition to size of the carbon number of the alcohol chain, the amount of branching is also significant the more linear isomers are of greater efficiency. 

DTDP > DIDP > DINP > DOP > DIHP > DBP. Higher molecular weight esters such as trimeUitates are even more thermally stable and trimeUitate esters find extensive use in the demanding cable specifications which have strict mass loss requirements. 

Studies on the use of high molecular weight esters in nitrile mbber have led to further studies to compare DINP with DBP. These showed that at the 10 phr level the nitrile mbber was effectively plasticized with DINP (35). 

Some typical applications in SFE of polymer/additive analysis are illustrated below. Hunt et al. [333] found that supercritical extraction of DIOP and Topanol CA from ground PVC increased with temperature up to 90 °C at 45 MPa, then levelled off, presumably as solubility became the limiting factor. The extraction of DOP and DBP plasticisers from PVC by scC02 at 52 MPa increased from 50 to 80 °C, when extraction was almost complete in 25 min [336]. At 70 °C the amount extracted increased from 79 to 95 % for pressures from 22 to 60 MPa. SFE has the potential to shorten extraction times for traces (<20ppm) of additives (DBP and DOP) in flexible PVC formulations with similar or even better extraction efficiencies compared with traditional LSE techniques [384]. Marin et al. [336] have used off-line SFE-GC to determine the detection limits for DBP and DOP in flexible PVC. The method developed was compared with Soxhlet liquid extraction. At such low additive concentrations a maximum efficiency in the extractive process and an adequate separative system are needed to avoid interferences with other components that are present at high concentrations in the PVC formulations, such as DINP. Results obtained... 

Table 3.21 Extraction of plasticiser (DOP, DINP) from flexible PVCa i>...

Other chemicals that are common in different RSL are phthalates. Phthalates are usually used as softening agents in plastics to obtain the required flexibility. The most common phthalates included on restriction lists for the leather industry are bis(2-ethylhexyl)phthalate (DEHP), benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), di- isononyl phthalate (DINP), D- isodecyl phthalate (DIDP) and di-n-octyl phthalate (DNOP). All these chemicals are included on the SVHC list (Candidate List), and currently (2012) there is a proposal to restrict the placing of products containing DEHP, BBP and DBP on the market in the EU. 

As well as aiding processing, a major function of plasticisers is to extend the operating temperature range by improving low temperature flexibility. The majority of demand in CR and NBR is satisfied by general purpose phthalate plasticisers di-2-ethylhexyl phthalate (DEHP), diisononyl phthalate (DINP) and diisodecyl phthalate (DIDP). However, a wide variety of speciality plasticisers, mainly esters, are marketed within the rubber industry. The majority of these have linear molecular structures giving them better low temperature performance than the phthalates. Examples of such plasticisers are di-2-ethylhexyl adipate (DOA), butyl carbitol adipate, di(butoxyethoxyethyl) adipate (BCA), and di-2-ethylhexyl sebacate (DOS). 

A decision by the European Parliament to put restrictions on the use of six phthalate plasticisers ignores scientific risk assessments and threatens the basis for Reach, the impending European legislation on chemical strategy. The Strasbourg parliament has voted to ban DEHP, DBP and BBP in children s toys and childcare items. DINP, DIDP and DNOP will be banned from use if the toys or items can be put in the mouth by children. An EU scientific risk assessment said children were not at risk from DINP in toys. A similar study in the US by the Consumer Product Safety Commission reached the same conclusion. European Commission... 

Phthalate esters orphthalates are molecules predominantly used in commerce to make plastic flexible. The substances produced in highest quantity, di(2-ethylhexyl) phthalate (DEHP or DOP), di-isononyl phthalate (DINP) and di-isodecyl phthalate (DIDP) are used almost exclusively as plasticisers in flexible PVC. Recently, these phthalates have been the focus of regulatory attention around the... 

Permanent bans on six phthalates in certain kinds of toys should replace the temporary ban in force for the past five years, EU Competitiveness Ministers agreed in September. Included in the proposed phthalates Directive, the provisions now face a second reading in the European Parliament. A common use of phthalates is as plasticisers to softenPVC. At the September meeting, Ministers agreed that three phthalates - DINP, DIDP and DNOP - should be banned at levels above 0.1% in toys and childcare articles intended to be sucked, while three others - DEHP, BBP and DBP - should be banned at the same level in all toys, regardless of whether they are intended for the mouth or of the age of child they are intended for. 

Leaders of the US Consumer Product Safety Commission (CPSC Bethesda, MD) have voted unanimously to deny a petition by environmental groups to ban the use of phthalates in soft PVC plastic toys intended for children aged five and younger. The three CPSC commissioners finalised 2002 recommendations last week that were submitted by the agency s staff following live years of study. The decision validates in particular the use of diisononyl phthalate (DINP), the primary plasticiser in PVC toys, ACC says. CPSC released a report in 2002... 

A recent report concerning the possible health hazards of di(2-ethylhexyl) phthalate (DEHP) and diisononyl phthalate (DINP), both used as plasticisers in flexible vinyl products has concluded that they are safe. This article supplies details of the general recommendations contained in the report. These emphasise the value of the plasticisers and strongly reinforce the need to be sure that regulatory decisions should be made based on sound science in a way that realistically assesses the likely exposure potential of adults and children. 

In April, an EC scientific committee concluded that there was reason for concern about estimated exposures of the phthalate DINP to toddlers chewing soft P VC toys. A study commissioned by the Dutch Health Ministry also failed to provide a robust defence of the plasticisers. Elsewhere, the Canadian Health Ministry has advised retailers to withdraw PVC teethers and find alternatives to soft PVC in other toddlers toys. Toys R Us has announced a worldwide withdrawal of teethers and other direct-to-mouth products containing phthalates. 

Scholz, N., Diefenbach, R., Rademacher, I., and Linnemann, D. Biodegradration of DEHP, DBF. and DINP poorly water soluble and widely used phthalate plasticizers. Bull. Environ. Contain. Toxicol., 58(4) 527-534, 1997. 

Di-isononyl phthalate DiNP MiNP metabolites with a keto oxo-MiNP... 

BBP benzyl-butyl phthalate, DBF di-butyl phthalate, DEHP di-(2-ethylhexyl) phthalate, DIDP di-iio-decyl phthalate, DINP di-iw-nonyl phthalate, DINCH di-iso-nonyl 1,2-cyclohexane di-carboxylic acid, DEHT di-(2-ethylhexyl) terephthalate DINP and DIDP were measured only in 62 dust samples... 

Some studies showed already that the levels of phthalate substitute s metabolites measured in human s urine are usually lower when compared to DEHP metabolites (Table 7) [105, 135]. However, such comparison should be carefully addressed since it was shown through rats exposure to such plasticizers that a considerable portion (about 50%) of the orally dosed DINP is excreted via the feces while it is known that DEHP is mainly extracted in humans via urine [105, 141]. 

Koch HM, Muller J, Angerer J (2007) Determination of secondary, oxidised di-iso-nonylphthalate (DINP) metabolites in human urine representative for the exposure to commercial DINP plasticizers. J ChromatogrB 847 114—125... 

European Union Risk Assessment Report (2003) 1,2-Benzenedicarboxylic acid, di-C8-10-branched alkyl esters, C9-rich and di- isononyl phthalate (DINP), European commission Joint Research Centre, EUR 20784 EN, Office for Official Publications of the European Communities... 

The global production of DEHP in 1994 was estimated to be between 1 and 4 million tons per year. The production volume of DEHP in Western Europe was 505,000 tons per year in 1997. In 2000, the European Union (EU) estimated a production of phthalates around 1 million ton per year in Western Europe (worldwide approximately 7 million tons), being DEHP the 60% of the production [36]. More recent information from industry shows that the use of DEPH in the EU has decreased to 221,000 in 2004, whilst the use of diisononyl phthalate (DiNP) and diisodecyl phthalate (DiDP) has increased during the same period. In fact, the annual production of DiNP in the EU in 2005 was estimated around 500,000 tons [37]. DiNP and DiDP are replacing DEHP as plasticizer because the use of DEHP has been limited due to it has been classified as CategorylA reprotoxin and it is included in the Annex XIV of the EU REACH legislation [38]. Between 1999 and 2004 the proportion of DEHP to total phthalate usage decreased from 42% to 22% and the proportion of DiNP and DiDP rose from 35% to 58% [37]. 

Di-n-octylphthalate (DnOP) is used primarily to produce flexible plastics. Diisononyl phthalate (DiNP) is actually a mixture of phthalates with branched alkyl side chains of varying length (C8, C9, and CIO). DiNP is primarily used (more than 95%) to produce flexible plastics and has been used to replace DEHP in some plastics. DiNP is now widely used in products such as children s toys, flooring, gloves, drinking straws, and garden hoses. The remaining 5% of DiNP is... 

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